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Saturday, December 24, 2011

EIA of Geothermal Projects in Iceland

Posted with permission from the Authors.

Proceedings World Geothermal Congress 2010

Bali, Indonesia, 25-29 April 2010

Environmental Impact Assessment of Geothermal Projects in Iceland

Albert Albertsson, Asbjorn Blondal, Bjorn H. Barkarson, Sigridur Dr. Jonsdottir and Stefan Gunnar Thors

HS Orka Ltd., Brekkustig 36, 260 Reykjanesbaer, Iceland. VSO Consulting, Borgartuni 20, 105 Reykjavik, Iceland,,,, Keywords: Environmental impact assessment, consultation, geothermal power plants.


There are some fundamental differences between energy projects in Iceland which have consequences for the efficiency and function of the EIA process. Most of the hydropower projects are well defined projects, i.e., the design, size and magnitude of the project is known when assessing the impact of the project. The characteristics of geothermal utilization can be very different. The utilization of geothermal energy is dynamic in nature, where the information is being gathered and processed continuously during the time of utilization. The paper discusses how the EIA Act and EIA process in Iceland function for geothermal projects and if it should be more flexible for such dynamic projects. The paper reviews geothermal projects, describing the main benefits and problems relating to the EIA process as well as the process of applying for consents and permits under various acts. The paper discusses possible solutions to the problems accounted for example using tools of planning, allowing more flexibility in the EIA, implementing more consultation among interest parties and agencies, and using area approach instead of structural approach.


Since the year 1993, the legislation and the process concerning environmental impact assessment (EIA) in Iceland, have been evolving. During this period, much emphasis has been on projects like hydropower plants and roads. The last few years more emphasis on geothermal development has cast a new light on the EIA process its purpose. Some points have proven positive and some have raised questions about whether the current process suits projects with dynamic nature like in the geothermal exploration and development. The purpose of this paper is to give some insight into the Icelandic EIA process and how it has been employed in the geothermal field.



In the year 1993 the Icelandic government legalized the EU Directive number 85/337/EBE with the Environmental Impact Assessment Act no. 63/1993 (EIAA). In the year 2000 a new EU directive (Directive 97/11/EB) came into effect and changes in the Icelandic EIAA followed. In the year 2005 the EIAA was changed once again but this time exclusively on the initiative of the Icelandic government.

2.1 The Environmental Impact Assessment Act and the

EIA Process

2.1.1 Geothermal Projects Subject to Assessment

Geothermal power stations and other thermal power installations with a heat output of 50 MW or more and other power producing units with an output of 10 MWe or more are always subject to an EIA.

In the year 2000 a more fundamental screening process was implied as part of the EIAA. Projects which may have substantial impacts on the environment are assessed on a case-by-case basis, regarding the nature, size and location to determine whether they shall be subject to an environmental impact assessment. For geothermal projects that fit into that category are deep drilling, in particular drilling of production wells and exploration wells in hightemperature geothermal regions.

In addition projects which are subject to an environmental impact assessment and are planned in the same area or are contingent upon one another may be assessed jointly, e.g. geothermal power station subject to assessment and the adjacent power lines.

2.1.2 Scoping Document

If a project is subject to an impact assessment the developer shall submit a scoping document. A scoping document contains a description of the project, the project site and alternatives which could be considered. The scoping document also proposes which aspects of the project and of the environment will be illustrated and what data will be gathered.

2.1.3 Initial Environmental Impact Statement (IEIS)

Following a scoping document the developer publishes a report on the project’s environmental impact assessment. This report, the initial environmental impact statement, has to be consistent with the scoping document.

In the IEIS the project’s possible environmental impacts, cumulative and synergic, direct and indirect are discussed.

2.1.4 Environmental Impact Statement (EIS)

An Environmental impact statement is the final report of the environmental impact assessment for a project. The statement is based on the IEIS and the consultation, opinions and comments from governmental agencies, municipalities and the public.

2.1.5 Review

All the previous steps are subject to review by the public,

public agencies and authorities. Within four weeks of

receiving the environmental impact statement, the National

Planning Agency (NPA) shall deliver a reasoned opinion on

whether the report meets the criteria of the EIAA and

whether the environmental impact is satisfactorily

described. The NPA’s opinion shall explain the main

premises of the assessment, including the quality of the data on which the assessment is based and its conclusions.

Figure 1: Number of geothermal development projects in Iceland assessed case-by-case whether they were subject to EIA 2000-2008.

2.2 Geothermal projects in Iceland and EIA

For the period 2000 to 2008, 29 geothermal development projects were assessed case-by-case whether they were subject to an EIA (Error! Reference source not found.).

Six of these projects were subject to an EIA of which five

were exploration drillings and one was due to changes in

current project development. The projects are all situated in

high temperature areas, on the southwest coast,

Reykjanesskagi and Hellisheiði, and on the northeast coast,

Krafla and Þeistareykir. One project of these 29 was

situated in low temperature area.From the year 1994 to

2008, 14 geothermal projects were subject to an EIA and

most of them during the last eight years. The first Icelandic

EIA undertaken for a geothermal project dealt with

exploration drilling. Some of the EIA cases are for one and

the same geothermal development project, due to

enlargement of an existing power plant or additional

drilling of production wells or reinjection wells. Since the year 2000 geothermal projects are 13% of the total EIA cases in Iceland.



For geothermal projects it is necessary to apply for various permits. The number of permits varies with the nature of the project, e.g. whether permits are applied for a power plant of some kind or for drilling production or exploration wells. Table 1 displays an overview of the application process for geothermal projects in Iceland, which permits are applied for and what legal body issues these permits. The process also includes changes in land use plans in the given area. The developer is responsible for applying for these permits.


Geothermal projects are different from most other projects that have to comply with the EIA act. Whereas for example hydropower plants can in a way been looked at as a static projects the geothermal projects are of a dynamic nature.

This is due to:

· Difficulties in long term and even short term

projection of the reservoir behavior

· Reinjection schemes, depending on a number of variables not known in the beginning of the exploration phase

· The exact location of facilities not exactly known and to a great extent depending on drilling results

· Number of drilling pads needed depending on the nature and evolution of the reservoir

· What impact earthquakes can have on the reservoir data not known

· Possible modifications of the steam/brine system and the power plant needed in case of steam cap development and/or effects of earth quakes

· Possible changes with time of the chemistry of the geothermal fluid

The information gathered in the exploration phase can have a significant effect on the size, location and the overall design of the project. Hence, the geothermal projects are dynamic not static as many other EIA projects such as hydropower projects, roads and aluminum smelters. Due to this, some have questioned whether the EIA process in Iceland takes into consideration this fundamental difference of the geothermal projects.

The time of preparation, exploration, research and engineering design of geothermal power plants is longer than for most other EIA projects. This is mainly due to the nature of the geothermal resource. Today it is common in Iceland that it takes 10 to 13 years to develop a geothermal green field project.

Due to the nature of the geothermal resource, the outcome of the different surveys undertaken at a very early stage of the project and which is the basic data for the EIA is just indicative for the real, short and long term impact the project imposes on the environment. The cost of the preparation and research is known to be considerable.

Geothermal developments need rather extensive exploration area as well as rather large area for production wells, reinjection wells and associated facilities. Today the tendency is to minimize the impact area as much as possible. This has in some cases led to very unfavorable and difficult operation of the geothermal field.

Table 1: Permits and Processes for Geothermal Projects in Iceland.

Geothermal projects are preferably developed in steps. The overall experience gained from the operation of a preceding step is the basis for the design of the succeeding step. In this way the evolvement with time of the geothermal reservoir and the technology is coped with. A succeeding step to one or several steps in operation can for example be increased steam production with associated increased reinjection for power generation or other industrial usage which in turn calls for more wells to be drilled and more facilities to be built. The very nature of geothermal projects is therefore dynamic in the sense that they are continuously evolving during the entire life span of the resource harnessed. In many cases these steps are also subject to an EIA.



Environmental impact resulting from geothermal development varies during the different phases of development and between sites. Kristmannsdóttir and Ármannsson (2003) have listed the main environmental issues involved in geothermal development:

· Surface disturbances

· Physical effects of fluid withdrawal

· Noise

· Thermal effects

· Chemical pollution

· Biological effects

· Protection of natural features

Geothermal exploration usually occurs in pristine areas characterized by volcanic activity, geothermal surface activity and geological formations. Ecosystems, both flora and fauna, are adapted to warm soils. Development includes roads, well pads and drilling of geothermal wells and groundwater and/or sea water wells. There is also deposition of waste soil and drill fluid including drill cuttings and mud. During flow testing of wells, steam and spray has shown to have temporarily adverse effect on the local vegetation with moss and grass being scalded. Noise follows flow testing of wells and can have negative effect on wildlife, tourists and local people.

If results from exploration are positive, development may continue. This can include more roads, well pads, pipelines, power plant, associated buildings and transmission lines. Geothermal power generation usually causes air pollution due to the emission geothermal gas from brine flashing, particularly carbon dioxide (CO2) and hydrogen sulfide (H2S), carbon dioxide adding to the greenhouse gas effect and hydrogen sulfide being poisonous in high concentration.

Gas concentration in emission varies to a great extent from one geothermal site to another. During operation, subsidence and induced seismicity are possible effects as is change in geothermal surface activity. Discharge of hot water and/or geothermal fluid from geothermal power generation can cause problems whereas the fluid can contain high concentration of various chemicals which may cause threat to living organs.



A few key issues should be noted from the brief history of EIA for geothermal projects in Iceland. This concerns the nature of geothermal projects, consultation in the EIA process, information and data concerning the key environmental factors affected by geothermal development and different vested interests in the geothermal development sites.

6.1 Consultation

6.1.1 Consultation Bodies

The EIA process for geothermal projects involves consultation with public agencies, local and governmental authorities, Non Governmental Organizations (NGO’s) and other stakeholders. By consulting with bodies involved in the EIA process at the early stages of each project, different views emerge which can be discussed and resolved before the project is fully developed.

In geothermal projects the Environment Agency, the National Energy Authority, local authorities, local Health Inspectorates, NGO’s and the Icelandic travel industry are considered as necessary consultation bodies. The National Planning Agency however plays a key role in the overall EIA process and should be consulted on regular basis.

6.1.2 Consultation during Scoping

Scoping document should be prepared in close consultation with the above mentioned parties. This is to ensure that all available data is included and that necessary research is planned for. Not doing so can cause delay and increase the cost of the project whereas research is time consuming and, in some instances, can only take place at a specific point in time of the year. This applies especially to ecological research. During preparation of scoping document meetings should be held where maps are presented and preliminary information regarding the project development is introduced, including energy output and input, effluent treatment, construction plans and available information on the development area.

Experience reveals that consultation does not need to be formal. Meetings can be informal but minutes of meetings are essential. These meetings can open up potential moments for deliberation. Matters discussed at consultation meetings should be addressed in the environmental impact statement.

6.1.3 Consultation for Environmental Impact Statement After reviewing research and exploration results and other

gathered data for a geothermal site, meetings with

consultation bodies should be arranged as often as

considered necessary. This allows for deliberation

concerning development of the overall project and

probable effects on the environment. This working

procedure usually raises questions at a point in time

in the development process when it is still possible

to make adjustments and plan for mitigation measures.

Developers and consultation parties do not always agree on what to emphasize on in the EIA but it is very important to address all those points at an early stage. The purpose of the EIA process is not halting the development of a project but to help public officials and the developer to make informed decisions that are based on an understanding of environmental consequences and take proper action before necessary permits are granted.

6.1.4 Consultation and Participation The main objective of public participation in the EIA process is that different views emerge and that all

stakeholders are involved in the decision-making. This does not necessarily lead to decisions that are beneficial for the environment but can help reaching reconciliation.

Public participation in the EIA process is developing in Iceland as well as elsewhere (Isaksson, 2009). A detailed framework does not exist on how this is best accomplished. Two geothermal EIA cases in Iceland show great disparity in public participation and interest.

The first case is the development of a new 135 MWe geothermal power plant in Hellisheidi area in year 2007. The proposed development is located in a scenic area with much geothermal activity on the surface. Gas emissions may cause negative impact on air quality and debate is on whether the harnessing can be considered sustainable. The EIA process sparked a lively discussion about the project. During the development of the environmental impact statement (EIS), a total of 675 individuals commented on the content of the document or the process of which 564 were unanimous. In addition a number of news articles were published.

In contrast during the EIA process for an 80-100 MWe enlargement of an existing geothermal power plant in Reykjanes in year 2009 no comment was given by the general public on the proposed project. This development was also intended in a scenic area with much geothermal surface activity, popular as tourist destination.

The reviewing process for both cases revealed a number of remarks from public agencies, local and governmental authorities including serious comments from the National Energy Authority.

The reason for this huge difference in public involvement is not clear but something sparked the interest in one case but not the other. It remains unclear whether many comments from the public deliver better grounds for making decisions concerning individual projects. Additionally, it can be questioned whether the EIA process is the right venue for such extensive paperwork. On the other hand, some have argued that the Icelandic public is prevented from influencing decisions regarding big projects which may affect the quality of their lives.

This experience gives reason and basis for development of a framework for public participation in the Icelandic EIA process. Its purpose should be a smooth development pathway, not to halt but to streamline a project. This framework could also take into consideration the different nature of projects.

The yes or no answer to a geothermal development question should be answered in a master plan, on national or regional basis and through strategic environmental assessment process (SEA). Land use policy should not be the challenge for the developers of individual projects.

6.2 Information

The issuing of geothermal research exploration permits and utilization permits must be based on reliable and detailed information about the projected impact the proposed project may have on the environment (Goff, 2000).

6.2.1 Geothermal Data and Sustainability

The management of geothermal energy as a natural resource is a vital issue in the EIA process. The assessment of sustainable use is a difficult task and controversy is among scientists, government agencies and developers how this is best accomplished. The conventional approach for the operation of a geothermal power plant is to increase steam production in steps while monitoring the effects on the reservoir. Developers’ point of view may be that in order to find out the long term capacity, fluid dynamics and thermodynamics of the reservoir it is necessary to tap the reservoir to such an extent and for a long enough period of time in order to get reliable response of reservoir variables for adjusting the reservoir model. Whereas this exercise is based on actual field trials for a long period of time with, in a way unforeseen results and uncertainty, it raises the question how to define a sustainable harnessing of the reservoir. Government officials, issuing permits, need to base their decisions on data at a very early stage of the project. They are responsible for the criteria for sustainable resource management. Presented with data, that shows pressure decline in the geothermal reservoir and pressure rise in the upper part of the system i.e. development of a steam cap, have created debate between parties on how and if to harness the geothermal reservoir.

In the EIA process for geothermal projects, this debate has become a larger part of the EIA deliberation. The knowledge and expertise of the nature and utilization of geothermal fields is limited to few professionals but the EIA process is intended to give the public the opportunity to follow this discussion. Everyone can reveal their opinion on this issue during the EIA process but only few scientists have the grounds to build their opinion on. Therefore, the scientific data, presented in the EIA and the debate between the geothermal specialists, may cause difficulty for public officials to understand and to make an informed decision. This makes the point that for the purpose of public participation in the EIA process, data must be presented in a clear and simple way. But this may be difficult due to the dynamic and unpredictable nature of the geothermal reservoir, as noted in chapter 3.

Therefore, the dialogue on whether the proposed resource harnessing can be considered sustainable, can only reach a certain point in the EIA process. The decision on whether a utilization permit or a harnessing permit is granted is not based on the EIA process but is the result of the communication of the developer and the Ministry of industry, energy and tourism / National Energy Authority (table 1). A development permit however is based on the EIA and the land use planning.

6.2.2 Geological Formations

Geological formations have been a key environmental factor

in the Icelandic EIA’s for geothermal projects. This is due to

the fact that geothermal activity is commonly associated

with volcanic activity, which is the source or origin of

geological formations. Many of these formations are

protected by the Nature Conservation Act, as landscapes

and ecosystems. This applies to volcanic craters, pseudo

craters and lava fields, as well as surface geothermal deposits

(sinter and travertine), 100 m2 or more in area.

Most geothermal developments influence to a certain degree the countenance of the landscape, i.e. the broad appearance of the landscape changes due to the alien facilities installed. Roads, production well heads, surface pipelines and buildings are examples of these aliens in nature.

Thanks to a technical development, the directional drilled wells have increased the flexibility in site selection for drilling. During the EIA process, this enables discussions between developers and geoscientists about the optimum locations and optimum numbers of well pads with associated service roads in order to minimize the environmental impact of the project.

Harnessing geothermal reservoirs causing pressure decline can change geothermal activity on the surface, causing geysers and hot springs to disappear or be transformed into fumaroles (Kristmannsdóttir and Ármannsson, 2003). This man made impact can be hard to distinguish from natural changes and can also happen in the course of seismicity. In the EIA it has been classified as indirect effect and is subject to great uncertainty.

This indirect impact due to tapping geothermal fluid out of the reservoir has called for development of mitigation measures like reinjection of geothermal fluid, establishing controlled and balanced harnessing of on the one hand the fluid dominated reservoir and on the other hand the steam cap once it is developed and proper monitoring of surface activity.

6.2.3 Geothermal Ecosystems

Ecosystems in geothermal areas are different from the surrounding ecosystems. These ecosystems can be considered unique in terms of biological diversity. They contain rare species of plants and moss, the microbial life in hot springs is very diverse and this also applies to the invertebrate species. Warm creek, originating from a hot spring, is different habitat than a cold creek close by. Consequently it also has different species composition. Geothermal development usually does not cause direct disturbance in these ecosystems. Directional drilling has also allowed for the protection of both fragile ecosystems as for rare geological formations. Nevertheless, the indirect effect on hot springs that may be caused by the geothermal harnessing, may lead to changes in these ecosystems. In recent EIA processes much attention has been given to this derivative impact on geothermal ecosystems. It can be argued that due to great uncertainty in predicting the effect of geothermal operations on hot springs this should not be given much weight in the EIA. On the other hand, these ecosystems are very susceptible and can be considered very important as components in Earths’ biodiversity.

It is also worth mentioning that the thermo files can be a valuable resource for the bio industry like the blue green algae, cultivated at the Blue Lagoon.

6.2.4 Tourism and Recreation

As mentioned above, geothermal exploration usually takes place in pristine areas characterized by volcanic activity. Many of these sites are categorized as of natural interest according to the Act of Nature Conservation and are popular as tourist destinations. Areas with good prospects for geothermal development are commonly popular as tourist destinations (Noorollahi and Yousefi, 2003). This has to some extent placed the tourist industry and the energy industry on opposite sides. The tourist industry claiming, geothermal development, including noise, surface disturbances and pipelines, will cause negative impact in popular tourist destinations. The geothermal developers on the other hand claiming the effect above ground occupying relatively confined area will be minor and that the tourist industry can´t claim any land use rights in these areas. The developers argue that gained experience proofs that visitor centers with educating exhibitions of the power plants and professionally guided tours attract every year thousands of visitors and therefore the geothermal installations can support the tourist industry.

Through consultation and problem solving some of these disputes can be resolved in the EIA process. This has been done through mitigation measures like minimizing visibility of buildings and pipelines, placing well pads far away from hiking trails, drilling many holes from each well pad and improving tourist facilities and hiking trails.

Opinion poll conducted in the Reykjanes area in Iceland has revealed positive view among tourists and recreational people towards geothermal power plants (Guðmundsson, 2008). When asked about steam released from a geothermal power plant the response was also positive. On the other hand, when asked about well sites and pipelines, the view was rather negative.

Kristmannsdóttir and Ármannsson (2003) also point out that there are not only negative effects of geothermal utilization to tourism. One of the most striking examples is the Blue Lagoon in Svartsengi high-temperature field, where a geothermal effluent pond is now one of Iceland’s most renowned tourist landmarks. Dumping water in this way would probably not be allowed today. Experience also shows that geothermal power plants attract tourists, scientists and students.

6.2.5 Uncertainty

As noted above there is certain degree of uncertainty regarding the imposed impact caused by harnessing of the geothermal reservoir on geothermal ecosystems and geothermal activity on the surface? The dynamic nature of the resource makes it even harder to identify human induces effects.

During the EIA process the ecosystems and the geothermal surface activity are usually identified and in the EIS it is stated that there may be some risk of negative impact caused by the project. In the recent projects, the developer is made fully accountable for this possible, indirect impact. This is partly based on the Precautionary Principle, which states that if an action or policy might cause severe or irreversible harm to the environment, in the absence of a scientific consensus that harm would not ensue, the burden of proof falls on those who would advocate taking the action. Instead of reaching consensus of lowering this risk by using mitigating measures like reinjection, this uncertainty has been used as grounds to halt further development. A study is being prepared to analyze and discuss how to apply uncertainty in the geothermal EIA cases.


The EIA process in Iceland is in continuous progress. Due to the dynamic nature of the geothermal resource, developers cannot at an early stage of development give decisive information on the scope of a given project, exact location of facilities and geothermal fluid extraction rate. Therefore one has endeavored to develop the projects in steps. This is not common for other EIA projects, and has caused some debate how to handle in the Icelandic EIA.

This also applies to the uncertainty of the environmental impact of geothermal development since all geothermal areas are dynamic in nature, causing natural fluctuations in surface activity and geothermal habitats.

The Icelandic EIA process needs to be further developed regarding geothermal development. Exploration zones must be defined in national and/or master plans so that adequate profile of the resource can be projected. Utilization zones also have to be defined adequately in master plans. This can include certain environmental conditions with regard to development, but must allow for some room for the developer to respond to information gathered from the reservoir.

The EIA process should evaluate the learning and experience gained from exploration and harnessing which can be of great value for research and development units, schools, educative tourism and the geothermal industry worldwide.

It must be looked into whether the grade scale used to assess the impact should be adapted further to fit for geothermal projects. A clear procedure must be set up how the grades are weighed together and how the weighted grade shall be used to arrive at the final decision in the EIS.

The EIA has created some vital benefits such as broad consultation and created new guidelines for the development of geothermal projects. It is important for all actors in the EIA process to learn from the experience gained from preceding steps and to improve the EIA process in general for geothermal projects, especially how to discuss and assess the uncertainty that is involved with all such projects and the complicated and diverse scientific data that the EIA decision is based on.


Goff, S., 2000. The effective use of environmental impact

assessments (EIAs) for geothermal development

projects. Proceedings World Geothermal Congress

2000. KyushuTohoku, Japan, May 28 – June 10.


Guðmundsson R., 2008. Ferdamenn og utivistarfolk a Reykjanesi 2007 (Tourists and Recreational People in Reykjanes 2007). Samantekt unnin fyrir VSO Consulting.RRF. 20 bls. In Icelandic.

Isaksson, K., T. Richardson and K. Olsson, 2009. From

consultation to deliberation? Tracing deliberative

norms in EIA frameworks in Swedish roads planning.

Environmental Impact Assessment Review, Volume

29, Issue 5, September 2009, Pages 295-304.

Kristmannsdottir, H. and H. Armannsson, 2003.

Environmental aspects of geothermal energy utilization.

Geothermics 32, 451-461.

Noorollahi, Y. and H. Yousefi, 2003. Preliminary

environmental impact assessment of a geothermal

Sunday, December 11, 2011

Cheap Solar Power Here Now

Solar Power Much Cheaper to Produce Than Most Analysts Realize, Study Finds

ScienceDaily (Dec. 7, 2011) — The public is being kept in the dark about the viability of solar photovoltaic energy, according to a study conducted at Queen's University.

"Many analysts project a higher cost for solar photovoltaic energy because they don't consider recent technological advancements and price reductions," says Joshua Pearce, Adjunct Professor, Department of Mechanical and Materials Engineering. "Older models for determining solar photovoltaic energy costs are too conservative."

Dr. Pearce believes solar photovoltaic systems are near the "tipping point" where they can produce energy for about the same price other traditional sources of energy.

Analysts look at many variables to determine the cost of solar photovoltaic systems for consumers, including installation and maintenance costs, finance charges, the system's life expectancy, and the amount of electricity it generates.

Dr. Pearce says some studies don't consider the 70 per cent reduction in the cost of solar panels since 2009 . Furthermore, he says research now shows the productivity of top-of-the-line solar panels only drops between 0.1 and 0.2 percent annually, which is much less than the one per cent used in many cost analyses.

Equipment costs are determined based on dollars per watt of electricity produced. One 2010 study estimated the this cost at $7.61, while a 2003 study set the amount at $4.16. According to Dr. Pearce, the real cost in 2011 is under $1 per watt for solar panels purchased in bulk on the global market, though he says system and installation costs vary widely.

Dr. Pearce has created a calculator program available for download online that can be used to determine the true costs of solar energy.

The Queen's study was co-authored by grad students Kadra Branker and Michael Pathak and published in the December edition of Renewable and Sustainable Energy Reviews.

Story Source:

The above story is reprinted from materials provided by Queen's University.

Note: Materials may be edited for content and length. For further information, please contact the source cited above.

Journal Reference:

  1. K. Branker, M.J.M. Pathak, J.M. Pearce. A review of solar photovoltaic levelized cost of electricity. Renewable and Sustainable Energy Reviews, 2011; 15 (9): 4470 DOI: 10.1016/j.rser.2011.07.104

Monday, November 7, 2011

The Ins and Outs of Solar Photovoltaics

Berkeley Lab Research Sparks Record-Breaking Solar Cell Performances

November 07, 2011

Theoretical research by scientists with the U.S. Department of Energy (DOE)’s Lawrence Berkeley National Laboratory (Berkeley Lab) has led to record-breaking sunlight-to-electricity conversion efficiencies in solar cells. The researchers showed that, contrary to conventional scientific wisdom, the key to boosting solar cell efficiency is not absorbing more photons but emitting more photons.

“A great solar cell also needs to be a great Light Emitting Diode,” says Eli Yablonovitch, the Berkeley Lab electrical engineer who led this research. “This is counter-intuitive. Why should a solar cell be emitting photons? What we demonstrated is that the better a solar cell is at emitting photons, the higher its voltage and the greater the efficiency it can produce.”

Yablonovitch holds joint appointments with Berkeley Lab’s Materials Sciences Division and the University of California (UC) Berkeley, where he is the James and Katherine Lau Chair in Engineering, and also directs the NSF Center for Energy Efficient Electronics Science. He is the corresponding author of a paper describing this work titled “Intense Internal and External Fluorescence as Solar Cells Approach the Shockley-Queisser Efficiency Limit.” Co-authoring this paper with Yablonovitch were Owen Miller of Berkeley Lab, and Sarah Kurtz, at the National Renewable Energy Laboratory.

In their paper, Yablonovitch, Miller and Kurtz describe how external fluorescence is the key to approaching the theoretical maximum efficiency at which a solar cell can convert sunlight into electricity. This theoretical efficiency, called the Shockley-Queisser efficiency limit (SQ Limit), measures approximately 33.5-percent for a single p-n junction solar cell. This means that if a solar cell collects 1,000 Watts per square meter of solar energy, the most electricity it could produce would be about 335 Watts per square meter.

Calculations by Miller, who is a member of Yablonovitch’s research group, showed that the semiconductor gallium arsenide is capable of reaching the SQ Limit. Based on this work, a private company co-founded by Yablonovitch, Alta Devices Inc., has been able to fabricate solar cells from gallium arsenide that have achieved a record conversion efficiency of 28.4 percent.

“Owen Miller provided an accurate theory on how to reach the SQ Limit that for the first time included external fluorescence efficiency,” Yablonovitch says. “His calculations for gallium arsenide showed that external fluorescence provides the voltage boost that Alta researchers subsequently observed.”

Berkeley Lab’s Eli Yablonovitch (left) and Owen Miller showed that counter-intuitively, a great solar cell also needs to be a great Light Emitting Diode. (Photo by Roy Kaltschmidt, Berkeley Lab)

Berkeley Lab’s Eli Yablonovitch (left) and Owen Miller showed that counter-intuitively, a great solar cell also needs to be a great Light Emitting Diode. (Photo by Roy Kaltschmidt, Berkeley Lab)

Solar or photovoltaic cells represent one of the best possible technologies for providing an absolutely clean and virtually inexhaustible source of electricity. However, for this dream to be realized, solar cells must be able to efficiently and cost-competitively convert sunlight into electricity. They must also be far less expensive to make.

The most efficient solar cells in commercial use today are made from monocrystalline silicon wafers and typically reach a conversion efficiency of about 23-percent. High grade silicon is an expensive semiconductor but is a weak collector of photons. Gallium arsenide, although even more expensive than silicon, is more proficient at absorbing photons, which means much less material is needed to make a solar cell.

“Gallium arsenide absorbs photons 10,000 times more strongly than silicon for a given thickness but is not 10,000 times more expensive,” says Yablonovitch. “Based on performance, it is the ideal material for making solar cells.”

Past efforts to boost the conversion efficiency of solar cells focused on increasing the number of photons that a cell absorbs. Absorbed sunlight in a solar cell produces electrons that must be extracted from the cell as electricity. Those electrons that are not extracted fast enough, decay and release their energy. If that energy is released as heat, it reduces the solar cell’s power output. Miller’s calculations showed that if this released energy exits the cell as external fluorescence, it would boost the cell’s output voltage.

“This is the central counter-intuitive result that permitted efficiency records to be broken,” Yablonovitch says.

Thin film solar cells fabricated from gallium arsenide have achieved a record sunlight-to-electricity conversion efficiency of 28.4 percent. (Image courtesy of Alta Devices, Inc.)

Thin film solar cells fabricated from gallium arsenide have achieved a record sunlight-to-electricity conversion efficiency of 28.4 percent. (Image courtesy of Alta Devices, Inc.)

As Miller explains, “In the open-circuit condition of a solar cell, electrons have no place to go so they build up in density and, ideally, emit external fluorescence that exactly balances the incoming sunlight. As an indicator of low internal optical losses, efficient external fluorescence is a necessity for approaching the SQ Limit.”

Using a single-crystal thin film technology developed earlier by Yablonovitch, called “epitaxial liftoff,” Alta Devices was able to fabricate solar cells based on gallium arsenide that not only smashed previous solar conversion efficiency records, but can be produced at well below the cost of any other solar cell technology. Alta Devices expects to have gallium arsenide solar panels on the market within a year.

“The SQ Limit is still the foundation of solar cell technology,” says Yablonovitch. “However, the physics of light extraction and external fluorescence are clearly relevant for high performance solar cells.”

Yablonovitch believes that the theoretical work by he and his co-authors, in combination with the performance demonstrations at Alta Devices, could dramatically change the future of solar cells.

“We’re going to be living in a world where solar panels are very cheap and very efficient,” Yablonovitch says.

This research was funded by a grant from DOE’s Light-Material Interactions in Energy Conversion Energy Frontier Research Center (LMI-EFRC).

# # #

Lawrence Berkeley National Laboratory addresses the world’s most urgent scientific challenges by advancing sustainable energy, protecting human health, creating new materials, and revealing the origin and fate of the universe. Founded in 1931, Berkeley Lab’s scientific expertise has been recognized with 13 Nobel prizes. The University of California manages Berkeley Lab for the U.S. Department of Energy’s Office of Science. For more, visit

Additional Information

For more information about the research of Eli Yablonovitch, visit the Website at

For more information about the LMI-EFRC, visit the Website at

For more information about Alta Devices, Inc., visit the Website at

Friday, November 4, 2011

Solar To Get Better and Cheaper


The Coolest New Solar Manufacturing Technology You’ve Never Heard Of

Publicly Funded Research Leads to Breakthrough in Solar Cell Production

SOURCE: NREL/Dennis Schroeder
The cavity inside the Solar Optical Furnace glows white hot during a simulated firing of a solar cell.

Too often, when talking about research and innovation on clean energy technologies, policymakers, pundits, and the media tend to assume that the biggest breakthrough will come from a completely novel technology. The discovery of some new and sexy clean energy technology will suddenly change the game and make clean energy abundant and affordable overnight.

In practice that rarely happens. A more likely scenario is that humble, behind-the-scenes “process innovations” will continue to increase the efficiency and drive down the costs of manufacturing the technologies we already know work.

The Department of Energy has recently completed testing on just such a humble breakthrough. The Optical Cavity Furnace is a new piece of equipment for making solar cells that is about to rock the photovoltaic industry by slashing costs and increasing efficiency. The news should not just excite tech nerds—by reducing the cost of producing solar cells by nearly three-quarters, this new technology represents another big step on the path to making clean energy the cheap kind of energy.

Here’s how it works. By using optics to more efficiently focus visible and infrared light, the Optical Cavity Furnace can heat silicon wafers used in solar cell production much more precisely and uniformly than previous forms of solar cell manufacture. The resulting solar cells are stronger, more efficient, and have fewer impurities. The National Renewable Energy Lab, or NREL, the DOE office responsible for the research, and a corporate partner AOS Inc. are now working to bring this technology to scale. The partners plan to build an industrial-scale Optical Cavity Furnace capable of producing 1,200 highly efficient solar cells per hour. NREL has cooperative research agreements with many of the country’s biggest solar cell producers.

Even better, in addition to producing solar cells more reliably, quickly, and therefore cheaply, the Optical Cavity Furnace itself is cheaper than traditional equipment used to produce cells. As the cost of manufacturing solar cells goes down, elementary economics suggests the accessibility of solar cells will soar. Then it’s a matter of harnessing their power in a myriad of other industries in a clean energy domino effect.

The White House has challenged the solar industry to produce clean electricity at $1 per watt. It has also set a national goal to achieve 80 percent clean energy use by 2035. Though some tout the idea that radically new breakthroughs in energy technology are needed to achieve these goals, incremental process innovation in existing technologies is perhaps a more important part of the solution. Innovations like the Optical Cavity Furnace that make the technologies we already know about cheaper, easier to produce, and more abundant can have game-changing impacts on bringing clean energy to scale.

The concept of “grid parity”—the point at which generating electricity from alternate energy sources is equivalent in cost to generating electricity from grid power—underlies the feasibility of using solar cells as a resource. Due to the competing forces of supply and demand, consumers likely will not choose clean energy until it is cheap and convenient. The good news is that researchers are racing toward that goal at an impressive rate.

In fact, the cost of photovoltaic, or PV, cells had already fallen 50 percent in the past two years prior to the DOE announcement. A June 2011 projection predicted PV module prices would hit the goal of $1 per watt by 2013; now the finish line of the proverbial “race to the bottom” seems even more imminent.

For consumers weary of the daily media promises of a cure-all solution to climate change, consider this: Deflating prices of solar cell manufacturing mirror the downward price slope of other technologies we now take for granted, like cell phones and DVD players. One important driver of those price declines is process innovation. And the government, instead of being an obstacle to competition, is uniquely poised to foster it, as evidenced by the new DOE solar furnace. In addition to the work being done at the Department of Energy’s National Renewable Energy Laboratory, dozens of other federal labs across the country under the DOE Office of Science, the National Institute of Standards and Technology, and the Manufacturing Extension Partnerships are helping push the bounds of process innovation in clean energy manufacturing.

The notion that science or innovation alone can solve our energy and climate challenges may seem like the overoptimistic ramblings of an enthusiastic technocrat. Yet new technologies like the Optical Cavity Furnace are piling up, creating a stronger and stronger rationale for increased federal investment in innovation. Through process innovation, we increase efficiency and lower costs, virtually negating the common arguments against climate-conscious energy policy. Like it or not, most consumers still make energy choices based on the impact those choices have on their wallets rather than based on the impact they have on the environment. With a vibrant national research ecosystem that fosters process innovation, before we know it, more and more consumers will be choosing clean energy not because it is the socially conscious choice but because it’s the cost-effective choice.

Thursday, July 21, 2011

The Best Centralized Solar Solution

Twice the height of the Empire State - EnviroMission plans massive solar tower for Arizona


11:03 July 21, 2011

EnviroMission's solar tower: coming to Arizona in 2015

EnviroMission's solar tower: coming to Arizona in 2015

Image Gallery (24 images)

An ambitious solar energy project on a massive scale is about to get underway in the Arizona desert. EnviroMission is undergoing land acquisition and site-specific engineering to build its first full-scale solar tower - and when we say full-scale, we mean it! The mammoth 800-plus meter (2625 ft) tall tower will instantly become one of the world's tallest buildings. Its 200-megawatt power generation capacity will reliably feed the grid with enough power for 150,000 US homes, and once it's built, it can be expected to more or less sit there producing clean, renewable power with virtually no maintenance until it's more than 80 years old. In the video after the jump, EnviroMission CEO Roger Davey explains the solar tower technology, the Arizona project and why he couldn't get it built at home in Australia.

How Solar Towers Work

Enviromission's solar tower is a simple idea taken to gigantic proportions. The sun beats down on a large covered greenhouse area at the bottom, warming the air underneath it. Hot air wants to rise, so there's a central point for it to rush towards and escape; the tower in the middle. And there's a bunch of turbines at the base of the tower that generate electricity from that natural updraft.

It's hard to envisage that sort of system working effectively until you tweak the temperature variables and scale the whole thing up. Put this tower in a hot desert area, where the daytime surface temperature sits at around 40 degrees Celsius (104 F), and add in the greenhouse effect and you've got a temperature under your collector somewhere around 80-90 degrees (176-194 F). Scale your collector greenhouse out to a several hundred-meter radius around the tower, and you're generating a substantial volume of hot air.

Then, raise that tower up so that it's hundreds of meters in the air - because for every hundred metres you go up from the surface, the ambient temperature drops by about 1 degree. The greater the temperature differential, the harder the tower sucks up that hot air at the bottom - and the more energy you can generate through the turbines.

    The advantages of this kind of power source are clear:
  • Because it works on temperature differential, not absolute temperature, it works in any weather;
  • Because the heat of the day warms the ground up so much, it continues working at night;
  • Because you want large tracts of hot, dry land for best results, you can build it on more or less useless land in the desert;
  • It requires virtually no maintenance - apart from a bit of turbine servicing now and then, the tower "just works" once it's going, and lasts as long as its structure stays standing;
  • It uses no 'feed stock' - no coal, no uranium, nothing but air and sunlight;
  • It emits absolutely no pollution - the only emission is warm air at the top of the tower. In fact, because you're creating a greenhouse underneath, it actually turns out to be remarkably good for growing vegetation under there.

The Arizona Project

While this is not the first solar tower that has been built (a small-scale test rig in Spain proved the technology more than a decade ago) EnviroMission has chosen to build its first full-scale power plant in the deserts of Arizona, USA.

The Arizona tower will be a staggering 800 metres or so tall - just 30 meters shorter than the colossal Burj Khalifa in Dubai, the world's tallest man-made structure. To put that in context - it will stand more than double the height of the Empire State building in New York City, and it'll be as much as 130 meters in diameter at the top. Truly a gigantic structure.

Currently undergoing site-specific engineering and land acquisition, EnviroMission estimates the tower will cost around US$750 million to build. It will generate a peak of 200 megawatts, and run at an efficiency of around 60% - vastly more efficient and reliable than other renewable energy sources.

The output has already been pre-sold - the Southern California Public Power Authority recently signed a 30-year power purchase agreement with EnviroMission that will effectively allow the tower to provide enough energy for an estimated 150,000 US homes. Financial modelling projects that the tower will pay off its purchase price in just 11 years - and the engineering team are shooting for a structure that will stand for 80 years or more.

Considering that a large city like Los Angeles requires total power in the region of 7,200 megawatts, you'd have to build a few dozen solar towers up to the same size as the Arizona project if you wanted to completely replace the existing, primarily coal-based energy supply for that city's 3.7 million-odd residents. So it's not an instant solution - but then, its short projected payback period and virtually zero operating costs make it a very sound economic proposition that competes favorably against other renewable sources.

Under the terms of the pre-purchase agreement, the Arizona tower is due to begin delivering power at the start of 2015. Watch this space!

Friday, April 22, 2011

Solar Adds Value To Home

Photovoltaic Systems Boost the Sales Price of California Homes

ScienceDaily (Apr. 21, 2011) — New research by the U.S. Department of Energy's (DOE) Lawrence Berkeley National Laboratory finds strong evidence that homes with solar photovoltaic (PV) systems sell for a premium over homes without solar systems.

"We find compelling evidence that solar PV systems in California have boosted home sales prices," says the lead author Ben Hoen, a researcher at Berkeley Lab. "These average sales price premiums appear to be comparable with the average investment that homeowners have made to install PV systems in California, and of course homeowners also benefit from energy bill savings after PV system installation and prior to home sale."

The research finds that homes with PV in California have sold for a premium, expressed in dollars per watt of installed PV, of approximately $3.90 to $6.40/watt. This corresponds to an average home sales price premium of approximately $17,000 for a relatively new 3,100 watt PV system (the average size of PV systems in the Berkeley Lab dataset), and compares to an average investment that homeowners have made to install PV systems in California of approximately $5/W over the 2001-2009 period.

"This is a sizeable effect," says Ryan Wiser, a Berkeley Lab scientist and co-author. "This research might influence the decisions of homeowners considering installing a PV system and of home buyers considering buying a home with PV already installed. Even new home builders that are contemplating PV as a component of their homes can benefit from this research."

Approximately 2,100 megawatts (MW) of grid-connected solar PV have been installed in the U.S. California has been and continues to be the country's largest market for PV, with nearly 1,000 MW of installed capacity. California is also approaching 100,000 individual PV systems installed, more than 90% of which are residential. Though an increasing number of homes with PV systems have sold, relatively little research has been performed to estimate the impacts of those PV systems on home sales prices.

The Berkeley Lab research is the first to empirically explore the existence and magnitude of residential PV sales price impacts across a large number of homes and over a wide geographic area. The research analyzed a dataset of more than 72,000 California homes that sold from 2000 through mid-2009, approximately 2,000 of which had a PV system at the time of sale. "This is the most comprehensive and data-rich analysis to date of the potential influence of PV systems on home sales prices," says co-author and San Diego State University Economics Department Chair Mark Thayer.

The research controlled for a large number of factors that might influence results, such as housing market fluctuations, neighborhood effects, the age of the home, and the size of the home and the parcel on which it was located. The resulting premiums associated with PV systems were consistent across a large number of model specifications and robustness tests.

The research also shows that, as PV systems age, the premium enjoyed at the time of home sale decreases. Additionally, existing homes with PV systems are found to have commanded a larger sales price premium than new homes with similarly sized PV systems.

"One reason for the disparity between existing and new homes with PV might be that new home builders also gain value from PV as a market differentiator that speeds the home sales process, a factor not analyzed in the Berkeley Lab study," says Berkeley Lab researcher and co-author Peter Cappers. "More research is warranted to better understand these and related impacts."

This work was supported by the Office of Energy Efficiency and Renewable Energy (Solar Energy Technologies Program) of the U.S. Department of Energy, by the National Renewable Energy Laboratory and by the Clean Energy States Alliance.

Download the full report, “An Analysis of the Effects of Residential Photovoltaic Energy Systems on Home Sales Prices in California”

Story Source:

The above story is reprinted (with editorial adaptations by ScienceDaily staff) from materials provided by DOE/Lawrence Berkeley National Laboratory.

Wednesday, February 23, 2011

All Energy From Solar in 20 Years?

Ray Kurzweil is arguably the world's most famous futurist. He laid out the law of accelerating returns, which states that technology improves at exponential rates, and made a string of dead-on predictions about computing in the 80s -- that a computer would beat a man at chess by 1998, and that the world would link networks into some crazy globally connected system sometime in the mid-90s. Now, Kurzweil is talking solar. In an interview with Grist, he explains why he's not worried about climate change, and how renewable energy sources will become dominant much, much sooner than we think.

He explains his techno-optimism to Grist:

One of my primary theses is that information technologies grow exponentially in capability and power and bandwidth and so on. If you buy an iPhone today, it's twice as good as two years ago for half the cost. That is happening with solar energy -- it is doubling every two years. And it didn't start two years ago, it started 20 years ago. Every two years, we have twice as much solar energy in the world. Today, solar is still more expensive than fossil fuels, and in most situations it still needs subsidies or special circumstances, but the costs are coming down rapidly ... we are only a few years away from parity.

So right now it's at half a percent of the world's energy. People tend to dismiss technologies when they are half a percent of the solution. But doubling every two years means it's only eight more doublings before it meets a 100 percent of the world's energy needs. So that's 16 years. We will increase our use of electricity during that period, so add another couple of doublings: In 20 years we'll be meeting all of our energy needs with solar, based on this trend which has already been underway for 20 years.

That's some major optimism indeed -- unfortunately, even if the technology itself got good enough that quickly, it in no way accounts for the massive task of deploying enough solar farms fast enough to render coal and natural gas plants obsolete. Many scientists say, after all, that we're going to need to drastically scale down emissions in 10 years time before we irrevocably alter our climate.

Furthermore, breakthroughs in clean energy technology have not occurred at an analogous rate to information tech -- they're much rarer, for a variety of reasons.

Finally, the most glaring miscalculation I think Kurzweil makes is that unlike the computing industry, there's an entrenched, powerful industrial opposition to clean energy that will actively work to stymie its advances whenever feasible in the political arena. Computers were developing into a wide open space in the market, with no comparable oppositional industry ready to compete with them -- the typewriter industry doesn't exactly have the same clout as the coal and oil industries. Perhaps if there wasn't a preexisting, artificially cheap energy source that was widely relied upon, and whose operators had access to major power levers, Kurzweil's time line could come true -- but since there is, we won't see the same kind of investment, excitement, and innovations in clean tech until use of dirty fuels is formally discouraged.

Kurzeil is right that we could power the world with clean energy in 20 years. But relying on technology alone isn't likely to get us there.

By Brian Merchant | Sourced from Treehugger

Comment By Jonathan Cole
For most of the past 30 years I have been living on solar and developing practical solar energy systems that provide energy for all of the modern amenities, are durable, low-maintenance and user-friendly. I never had a power outage or burned out even a light bulb.

This technology, properly designed and installed already competes with the grid even without any subsidy. Why? Because once the equipment is installed, the fuel is free. Since a properly made system can last from 25 to 40 years, you save a lot of money on avoided fuel costs. I don't pay any electrical bill and am totally independent of the grid. I have all modern amenities.

The reason Kurzweil is correct and the author of the article is dubious, is because the author has his facts wrong. Computers and the internet have had huge resistance from entrenched change-averse interests in the publishing, entertainment, telecommunications and other industries whose bottom lines are being destroyed by the new technologies.

There is a way to do a complete end-run around the utility monopolies/oligarchies who are certainly dragging their feet in many instances. That is to create an integrated solar energy appliance that is mass-producible, just like the computer is a mass-producible integrated information processing appliance.

That has yet to be done because the world is currently in a frenzy of speculation instead of productive investment. While a certain amount of speculation may play a healthy role in an economy, an absolutely uncontrolled speculative frenzy, destroys wealth and reduces the productivity required for progress.

We need visionary investors who realize the importance of productive investment to support the development of these integrated solar appliances. Once a UL approved solar energy appliance is developed that can be plugged into the home with a minimum of red-tape, the power industry will be forced to join in or be rendered obsolete.

And by the way, to do this requires nothing to be invented, only adapted and refined. So based on experience, knowledge and facts, Kuzweil's prediction is totally on track. Jonathan Cole, MBA http://lightontheearth.blogspo.../