Policy instruments to promote good practices in bioenergy feedstock production March 2012

Modern bioenergy development, through its environmental and socio-economic impacts, may have positive or negative effects on the four dimensions of food security: availability; access; utilization, and stability.
In order to ensure that modern bioenergy development is sustainable and that it safeguards food security, a number of good practices can be implemented throughout the bioenergy supply chain. Building on FAO’s work on good practices in agriculture and forestry, the Bioenergy and Food Security Criteria and Indicators (BEFSCI) project has compiled a set of good environmental practices that can be implemented by bioenergy feedstock producers in
order to minimize the risk of negative environmental impacts from their operations, and to ensure that modern bioenergy contributes to climate change mitigation while safeguarding and possibly fostering food security. BEFSCI has also compiled a set of good socio-economic practices that can help minimize the risks and increase the opportunities for food security associated with bioenergy operations.
Most of the good practices that BEFSCI has compiled present various challenges and there are a number of both economic and non-economic barriers to their implementation. If proper policy instruments and incentives are not in place, the costs of implementing these practices might be too high for producers.
BEFSCI has identified a range of policy instruments that can be used to require or promote – either directly or indirectly – good environmental and socioeconomic practices in bioenergy feedstock production, and to discourage bad practices.
These instruments can be grouped into four main categories:
• mandates with sustainability requirements
• national standards for certification
• financial incentives
• capacity building
An overview of these instruments, and examples of their application in bioenergy (where available) or agriculture, are provided in this policy brief.
The viability and effectiveness of these instruments in a certain country will depend on a number of factors, including the financial resources available, and the administrative and enforcement capacity of the government.

By: A. Rossi, P. Cadoni (FAO)
Algal biorefinery-based industry: an approach to address fuel and food insecurity for a carbon-smart world September 2010

Food and fuel production are intricately interconnected. In a carbon-smart society, it is imperative to produce both food and fuel sustainably. Integration of the emerging biorefinery concept with other industries can bring many environmental deliverables while mitigating several sustainability-related issues with respect to greenhouse gas emissions, fossil fuel usage, land use change for fuel production and future food insufficiency. A new biorefinery-based integrated industrial ecology encompasses the different value chain of products, co-products, and services from the biorefinery industries. This paper discusses a framework to integrate the algal biofuel-based biorefinery, a booming biofuel sector, with other industries such as livestock, lignocellulosic and aquaculture. Using the USA as an example, this paper also illustrates the benefits associated with sustainable production of fuel and food. Policy and regulatory initiatives for synergistic development of the algal biofuel sector with other industries can bring many sustainable solutions for the future existence of mankind.

By: Bobban Subhadraa, Grinson-George
Current status and potential for algal biofuels production August 2010

It seems probable that growth in human population, future climate change effects on freshwater resources, which are already stressed in some regions, and eventual shortages of unutilized arable land will encourage the exploitation of microalgae based production systems for both food and fuel. Claims that the ability to utilise non-arable land and waste water resources with few competing uses make algal biofuel production systems superior to biofuels based on terrestrial biomass has created great interest in governments, NGOs, the private sector and the research community. Current initiatives clearly indicate this interest at all levels of government and the in private sector in the development of algal biofuels technologies and enterprises.
This report examines the technology and economics of biofuel production from oil forming autotrophic microalgae. The context of this examination is an assessment of the likely contribution of algae derived biofuel to the world‘s future liquid transportation fuel needs. The current status of the technology is reviewed in section 2 of this report. The technology review covers algal biology, cultivation, harvest, extraction and conversion to liquid transport fuels. The sustainability of algal biofuel production systems is discussed in section 3 and the site requirements for large scale intensive pond algal production are considered in section 4. Section 5 presents economic analyses, which among other things explores the influence of proximity of resources to production sites. Section 6 addresses the likely contribution of algal biofuels to future liquid transportation fuel markets. The report also contains a number of appendices that contain a review of US algal biofuel research, development and demonstration, algal culture collections, the underlying assumptions and material balances used in the economic model (in section 5) and a photographic collection.

By: A. Darzins, P. Pienkos (NREL), L. Edye (BioIndustry Partners)
Algae-based biofuels: applications and co-products July 2010

The possible competition for land makes it impossible to produce enough first generation biofuel to offset a large percentage of the total fuel consumption for transportation. As opposed to land-based biofuels produced from agricultural feedstocks, cultivation of algae for biofuel does not necessarily use agricultural land and requires only negligible amounts of freshwater, and therefore competes less with agriculture than first generation biofuels. Combined with the promise of high productivity, direct combustion gas utilization, potential wastewater treatment, year-round production, the biochemical pathways and cellular composition of algae can be influenced by changing cultivation conditions and therefore tailored on local needs. On the other hand, microalgae, as opposed to most plants, lack heavy supporting structures and anchorage organs which pose some technical limitations to their harvesting.
The reasons for investigating algae as a biofuel feedstock are strong but these reasons also apply to other products that can be produced from algae. There are many products in the agricultural, chemical or food industry that could be produced using more sustainable inputs and which can be produced locally with a lower impact on natural resources. Co-producing some of these products together with biofuels, can make the process economically viable, less dependent from imports and fossil fuels, locally self sufficient and expected to generate new jobs, with a positive effect on the overall sustainability.
This document provides an overview of practical options available for co-production from algae and their viability and suitability for developing countries.

By: Food and Agriculture Organization of the United Nations (FAO)
Algae biofuel - Special report June 2010

Algae Biodiesel:

answers from an Interview with OriginOil CEO Riggs Eckelberry.

Algae: The ultimate biofuel? April 2010

With traditional biofuels under fire for driving up food prices and wreaking environmental havoc, industrialists are stepping up research into algae as a sustainable alternative - but many obstacles remain before algae oil finds its way into our cars and planes.

EU Milestones:


Dec. 2008: EU leaders agree revised directive on renewable energy, agreeing a 10% target for 'green fuels' by 2020 (EurActiv 5/12/08).5 Dec. 2010: Deadline for all EU countries to comply with new Renewables Directive. Greenhouse gas savings from biofuels to reach minimum 35%.2012: EU countries to submit first report on national measures taken to respect the sustainability criteria for biofuels.By Dec. 2014: Commission to review greenhouse gas emission saving thresholds for biofuels, taking available technologies into account.2017: Greenhouse gas savings from biofuels to reach minimum 50%.2018: Greenhouse gas savings from biofuels to reach minimum 60%.2018: Commission to present renewable energy roadmap for post-2020 period.2020: Transport sector mandated to source 10% of its energy needs from renewable energy, including sustainable biofuels and others.


In December 2008, the EU struck a deal to satisfy 10% of its transport fuel needs from renewable sources, including biofuels, hydrogen and green electricity, as part of negotiations on its energy and climate package (EurActiv 05/12/08).

"The mandatory 10% target for transport to be achieved by all member states should […] be defined as that share of final energy consumed in transport which is to be achieved from renewable sources as a whole, and not from biofuels alone," says the final text of the EU Renewables Directive.

The new directive obliges the bloc to ensure that biofuels offer at least 35% carbon emission savings compared to fossil fuels. The figure rises to 50% as of 2017 and 60% as of 2018.

The conditionality is linked to increasing concerns about the sustainability of the so-called first-generation biofuels currently available - such as biodiesel and bioethanol - which are made from agricultural crops (including corn, sugar beet, palm oil and rapeseed).

The directive also states that the EU should take steps to promote "the development of second and third-generation biofuels in the Community and worldwide, and to strengthen agricultural research and knowledge creation in those areas".

By: EurActiv.com
Algae – The future for bioenergy? March 2010

This publication provides the summary and conclusions from the workshop ‘Algae – The Future for Bioenergy?’ held in conjunction with the meeting of the Executive Committee of IEA Bioenergy in Liege, Belgium on 1 October 2009.
The purpose of the workshop was to inform the Executive Committee of the potential for using algae for energy purposes by stimulating a discussion with experts working both within and outside the Agreement. The workshop aimed to assess the current state-of-the-art, to consider the potential in the medium and long term, and to identify the major research and commercialisation challenges.

By: IEA Bioenergy
Oilgae guide to algae-based wastewater treatment – Sample report November 2009

Algae are important bioremediation agents, and are already being used by many wastewater facilities. The potential for algae in wastewater remediation is however much wider in scope than its current role.
The Oilgae Guide to Algae-based Wastewater Treatment was prepared by Oilgae as a response to the need in the market for a detailed resource that provides a compendium of practical data, insights and case studies for algae-based wastewater treatment efforts worldwide.
The focus of the report is to provide guidance that can facilitate actions on the part of the academia and the commercial sector. Hence, inputs and data that have been provided have a slant towards real life case studies and experiments.
While the thrust of the report is on wastewater bioremediation using algae, the report also provides detailed references on deriving biofuels from algae. Algae are currently researched for their ability to be the potential feedstock for biofuels. Combining algae biofuels with wastewater remediation provides significant economic synergies for the process.
This document is a summary (sample report) of the full Oilgae Guide to Algae-based Wastewater Treatment.

By: Oilgae
The promise of algae biofuels October 2009

To properly assess algae biofuels, there is a need to see the big picture—to develop the full life cycle of algae-to-biofuel production and analyze all potential impacts. This is especially important for a technology that we hope will contribute on a meaningful scale to meeting our transportation energy needs.
This report provides an overview of the potential positive and negative environmental externalities of algae biofuel processes and technologies. In doing so, we hope to provide a methodology and logic that can be used in the future to analyze all inputs and outputs associated with every potential process in an algae-to-biofuel production pathway. Specifically, the report identifies key environmental issues to be considered across all stages of an algae biofuel production; proposes a mapping framework for these algae-to-biofuel pathways; summarizes what is known and unknown about the potential environmental impacts of each algae-to-biofuel process; and identifies areas of future research need and recommends policy and industry actions to improve the environmental sustainability of the industry and its fuel production practices.

By: Terrapin Bright Green LLC, Natural Resources Defense Council
Review by the Jatropha Alliance of the Swiss Aid Study: „Jatropha! – A socio-economic pitfall for Mozambique“ August 2009

The study “Jatropha! – A socio-economic pitfall for Mozambique” prepared by Justiça Ambiental (JA) et União Nacional de Camponeses (UNAC) for Swiss Aid (referred in the following to as Swiss Aid Study) provides a very one-sided and negative picture of the Jatropha sector in Mozambique. The Jatropha Alliance therefore felt obliged to review the arguments put forward by the authors, and in short, the results are as follows:
• The study lacks scientific scrutiny
• The study criticizes claims that are not made by serious Jatropha growers and experts, i.e. it constructs “silhouette targets” that do not exist in reality
• The study presents imprecise arguments and depicts only the negative aspects and ignores well-established advantages of Jatropha cultivation
The details of their analysis are given in this paper.
The Jatropha Alliance strongly believes that the results of the study cannot be substantiated, and its conclusions are false to a very large extend. They urge the authors to revisit their arguments and we call on the public and the media not to distribute these false claims to a wider audience.
The members of the Jatropha Alliance – some of which also operate in Mozambique – all commit to the principles of the Roundtable on Sustainable Biofuels, which has already set a comprehensive framework for sustainable production of biofuels after a year-long global stakeholder process. They therefore see the picture drawn in this study as detrimental to our continued striving for the ecologically, socially and economically responsible cultivation of Jatropha.

By: Jatropha Alliance
Cellulosic ethanol and advanced biofuels investments June 2009

There's much excitement about second generation biofuels made from cellulosic feedstocks and algae, be they cellulosic ethanol, biodiesel, biocrude, or electricity from biomass.  There will be winners, but they may not be the technology companies.

At the 2009 Advanced Biofuels Workshop, there were two major themes: developing new feedstocks, especially algae, and the development of new pathways to take biomass into products such as biocrude, which can be used in exiting oil refineries.

The current federal Renewable Fuel Standard requires the use of 36 million gallons of biofuels, including at least 21 billion gallons of advanced biofuels by 2022.  Advanced biofuels are defined as fuels other than corn-based ethanol and with greenhouse gas (GHG) emissions half that of the fuel they replace.  This creates a gigantic market, so large that some industry observers doubt if it can be met.

Many of these fuels will not be ethanol, a fuel which poses problems with the current fuel transport and distribution infrastructure.  Even for cellulosic ethanol, there are several different processes that different companies are pursuing: Acid hydrolysis, Thermochemical conversion, Biochemical conversion, and Consolidated Bioprocessing, and combinations of these three used in various combinations by various companies.  

Potential products not only include fuels such as ethanol, butanol and higher-carbon alcohols, but biocrude which can be fed into existing refineries.  Other potential products include plastics, and many other products currently produced by the petroleum based energy industry.  

The bewildering array of potential pathways and products make for a very challenging investment landscape.  An investor in any company would need a lot of confidence that the company they are investing in will be able to take their chosen feedstocks to a potential salable product at lower cost than all the competitors out there.  Unsurprisingly, nearly every company feels it has the best process.

By: Tom Konrad, Ph.D., CFA
Algae-based biofuels: a review of challenges and opportunities for developing countries May 2009

Algae have recently received a lot of attention as a new biomass source for the production of renewable energy. Some of the main characteristics which set algae apart from other biomass sources are that algae can have a high biomass yield per unit of light and area, can have a high oil or starch content, do not require agricultural land, fresh water is not essential and nutrients can be supplied by wastewater and CO2 by combustion gas.
The first distinction that needs to be made is between macroalgae (or seaweed) versus microalgae. Microalgae have many different species with widely varying compositions and live as single cells or colonies without any specialization. Although this makes their cultivation easier and more controllable, their small size makes subsequent harvesting more complicated. Macroalgae are less versatile, there are far fewer options of species to cultivate and there is only one main viable technology for producing renewable energy: anaerobic digestion to produce biogas.
Both groups will be considered in this report, but as there is more research, practical experience, culture and there are more fuel options from microalgae, these will have a bigger share in the report.
In chapter 2, the different technological components that make up Algae Based Biofuels (ABB) are discussed: algae cultivation technology; processing to biofuel options; locations and carbon; light and nutrient inputs. Both land based and sea based applications are discussed.
In chapter 3, ABB sustainability is investigated in depth. First, existing biofuel sustainability standards are analysed for applicability, followed by a thorough analysis of the opportunities and risks of ABB sustainability. Secondly, sustainability is discussed in the context of potential and threats for developing countries.

By: Food and Agriculture Organization of the United Nations (FAO)
Greenhouse gas sequestration by algae. Energy and greenhouse gas life cycle studies - Proceedings of the 6th Australian Conference on Life Cycle Assessment March 2009

This paper assesses the greenhouse gas, costs and energy balance on a life cycle basis for algae grown in salt water ponds and used to produce biodiesel and electricity.
Under the conditions described and data assumed in the paper, it is shown that it is possible to produce algal biodiesel at less cost and with a substantial greenhouse gas and energy balance advantage over fossil diesel.
The report cautions that translating science into continuous commercial-scale production has not yet been achieved with algae, but also pointed out that algae farms can create up to 37 jobs per 1,000 acres in algae production, and determined that a plant of that size could be economically feasible.

By: P. K. Campbell, T. Beer, D. Batten
A review of the potential of marine algae as a source of biofuel in Ireland February 2009

This report, commissioned by Sustainable Energy Ireland, provides an overview of algae as an energy resource, from either marine macroalgae or microalgae. It is also assess the potential resource in Ireland, determine the level of activity and recommend research and development priorities.
The focus of this report is the main biomass resources in the marine environment - marine algae, either macroalgae (seaweeds) or microalgae (phytoplankton). Freshwater species were excluded from the brief.
The scope of the study adheres generally to the original tender request, which includes the following key items which are addressed within the report:
• Review international developments in marine algae as a source of biofuels
• Identify technologies to grow, harvest and convert marine algae to biofuel
• Present illustrative examples
• Highlight barriers to commercialisation which need to be addressed
• Identify co-product/residue issues
• Provide outline cost estimates for commercial projects
• Identify potential applications in the Irish context
• Highlight factors that favour a site for algae production and the types of algae that might be suitable
• Estimate the potential for development to 2020
• Identify important research topics in order to realise potential for biofuel from marine algae in Ireland
The report contents have been set out in logical sections as set out below, in addition to this introductory section.
• Section 2: This section sets out a supply-chain review in order to give a complete picture of the resources, technologies and barriers to commercialisation. Case studies are elaborated for macroalgae and microalgae.
• Section 3: This covers costs and productivity estimates. There is no existing commercial technology. The estimates are not based on reliable data in an Irish context, and for this reason are set out as a stand-alone section.
• Section 4: This estimates the potential for development in Ireland, where factors favouring (or limiting) production in Ireland are outlined and tentative roadmaps out to 2020 described for macroalgae and microalgae.
• Section 5: This section outlines a number of research programmes and commercial developments, building on earlier sections to present a point in time overview. This highlights the international context within which any Irish projects must be viewed and the need for collaborative research.
• Section 6: The research priorities which need to be addressed in order to commercialise marine algae for biofuel are outlined. This is done by first addressing issues globally and then by attempting to identify specific priorities for an Irish R&D programme.
• Section 7: Draws some overall conclusions and highlights the principal findings of the report.

By: Sustainable Energy Ireland (SEI)
Microalgae technologies and processes for biofuels/bioenergy production in British Columbia - Current technology, suitability and barriers January 2009

Extensive review of the literature and information obtained from industry insiders resulted in the identification of cost parameters for expected biomass yields, algal oil content, capital, labour and operational costs. A thermodynamic model was developed that uses hourly solar insulation and temperature values in British Columbia (BC) to predict maximum biomass yields for the two phototrophic technologies. Using this model, the resulting cost per litre of algae oil produced was determined.
The results of the economic analysis for each scenario, expressed both in terms of costs ($) per kg of biomass produced and in cost per litre of oil produced are reported. One option to produce ethanol in PBR was also included. For comparison, the cost per kg of canola, and cost per litre of canola oil are included.
The base case costs for the three different production processes are shown. Raceways have total production costs of $14.44 per litre of algal oil. The majority of this cost is capital (49%) and labour costs (27%). However, operational costs, such as power and fertilizer, are also substantial (25%). PBRs have higher production cost of $24.60 per litre of algal oil. As with raceways, the majority of this cost is capital (63%). Fermenters have the lowest production cost of $2.58 per litre of algae oil. This time the majority of cost is operational (78%) – mainly from the power (31%) and the organic carbon substrate (23%).
Even under optimistic scenarios currently none of the processes examined in this study can achieve price parity with fossil fuels. Furthermore, while fermentation appears closest, achieving cost-effective algal biomass production through fermentation still requires significant R&D to generate greater yields and oil content.

By: A.O. Alabi (Seed Science Ltd), M. Tampier (ENVINT), E. Bibeau (Univ of Manitoba)
A review on culture, production and use of spirulina as food for humans and feeds for domestic animals December 2008

During the sixtieth session of the United Nations General Assembly (Second Committee, Agenda item 52), a revised draft resolution on the “Use of spirulina to combat hunger and malnutrition and help achieve sustainable development” was submitted by Burundi, Cameroon, Dominican Republic, Nicaragua and Paraguay. As a follow up of this resolution, FAO was requested to prepare a draft position paper on spirulina so as to have a clearer understanding on its use and to convey FAO’s position on this.
The primary objective of this review is to assess/evaluate the existing knowledge on the culture, production and use of spirulina for human consumption and animal feeds and to prepare the draft position paper on the use of spirulina.
The review is primarily a desk study based on secondary-sources of information/data derived from published literature and unpublished reports and primary-sources of data/information collected through suitable consultations with those associated with culture/production and use of spirulina.

By: FAO
Opportunities and challenges in algae biofuels production October 2008

The cultivation of microalgae for biofuels in general and oil production in particular is not yet a commercial reality and, outside some niche, but significant, applications in wastewater treatment, still requires relatively long-term R&D, with emphasis currently more on the R rather than the D. This is due in part to the high costs of even simple algae production systems (e.g. open, unlined ponds), and in even larger part to the undeveloped nature of the required algal mass culture technology, from the selection and maintenance of algal strains in the cultivation systems, to achievement of high productivities of biomass with a high content of vegetable oils, or other biofuel precursors.

By: J. Benemann
GreenAlgae Strategy September 2008

Green Algae Strategy shares the fascinating story of extraordinary innovation occurring not in deep space or in deep oceans but simply under our feet. Few people are aware that this simplest of organisms holds such great potential for desperately needed sustainable solutions for our very hungry, thirsty and needy planet.
The Green Algae Strategy engineers hope for a better life for billions of people who lack sufficient and affordable food, fresh water, fresh air, fertilizer and fuel for cooking and heating fires. The strategy includes cleaning polluted water and reforesting denuded land but those objectives are peripheral to the focus here on producing sustainable foods and biofuels. Since algae-based biofuels provide the strongest financial incentives for R&D, new food sources, pollution solutions, reforestation, medicines and other coproducts will all benefit from breakthroughs in algal production systems for biofuels.
Biotechnology applies science and engineering principles to living organisms to solve problems and to make useful products. Over the last century, many people and companies have lost fortunes trying to create commercial scale algal production. The laboratory studies are so promising, yet even modest scale field studies have typically become unmanageable, unstable and unproductive.
Advances in biotechnology, nanotechnology and chemical and mechanical engineering have changed the production landscape for algae from dismal to terrific. Green Algae Strategy lays out a roadmap for what may be the challenge of this century: solutions to sustainable food, water, pollution, reforestation and biofuels.
Algae will not be the silver bullet that singularly resolves sustainability issues. Truly renewable technologies that meet increasing world demand for food and energy will be solved by a portfolio approach that will include all renewable energy sources and biofuels. However, algae are poised to provide innovative, high value and engaging solutions.

By: Mark Edwards
Biodiesel from algae oil July 2007

Currently most research into efficient algal oil production is being done in the private sector, but if predictions from small scale production experiments bear out then using algae to produce biodiesel may be the only viable method by which to produce enough automotive fuel to replace current world gasoline usage, according to U.S. Department of Energy. [4] In the short term, a handful of early-stage companies working on algae want to produce Algae oils for biodiesel production, replacing a significant proportion of the diesel fuel that currently serves about one-third of transport needs in the United States.
Research into algae for the mass-production of oil is mainly focused on micro-algae. The preference towards micro-algae is due largely to its less complex structure, fast growth rate, and high oil content. Some species of algae are ideally suited to biodiesel production due to their high oil content – sometimes topping out near 50%. Some commercial interests into large scale algal-cultivation systems are looking to tie in to existing infrastructures, such as coal-fired power plants or sewage treatment facilities. This approach not only provides the raw materials for the system, such as CO2 and nutrients; but it changes those wastes into resources.
This document provides a brief overview of the main challenges related to the algal biofuel sector and provides a list of enterprises directly involved in the research and development of related technologies.

By: L. Wagner
The controlled eutrophication process: using microalgae for CO2 utilization and agricultural fertilizer recycling August 2002

In 1960, Oswald and Golueke presented a conceptual techno-economic analysis, "The Biological Transformation of Solar Energy", proposing the use of large-scale raceway ponds to cultivate microalgal on wastewater nutrients and then to anaerobically ferment the algal biomass to methane fuel. The methane was to be converted into electricity, with the CO2-containing flue gas recycled to the ponds to support algal production. Over the past forty years a great deal of research has been carried out on this and similar concepts for microalgae fuels production and CO2 utilization. However, major technical challenges have limited the practical application of this technology: the difficulties of maintaining selected algal species in large-scale production systems, the lower-than anticipated biomass productivities and methane yields, and the high costs of harvesting the algal biomass and of the overall process. These limitations can, however, be overcome by applying such processes where additional economic benefits, such as wastewater treatment or nutrient recovery, are available and where relatively large systems (> 100 hectares) can be deployed, allowing economics of scale.
One such site is the Salton Sea in Southern California, into which over 10,000 tons of nitrogen and phosphate fertilizers are discharged annually by three small rivers draining large tracts of irrigated agriculture. Removal of nutrients from these inflows is required to avoid eutrophication of this large (some 900 km2), shallow, inland sea, with resulting massive algal blooms, fish kills and other environmental impacts. Nutrient capture could be accomplished with some 1,000 hectares of algal pond systems, with the algal biomass harvested and converted into fuels and the residual sludge recycled to agriculture for its fertilizer value. A techno-economic analysis of this process, based on nutrient removal defraying a fraction of the costs, suggests that such a process could mitigate several hundred thousand tons of fossil CO2 emissions at below $10/ton of CO2-C equivalent.

By: J.R. Benemann, J.C. Van Olst, M.J. Massingill, J.C. Weissman, D.E. Brune
Microalgae production from power plant flue gas: environmental implications on a life cycle basis June 2001

CO2 is a major greenhouse gas (GHG), and its physical capture from fossil-fuel power-plants has been considered as a potential remediation option since Marchetti (1977) first proposed the disposal of the captured CO2 in the deep ocean. Several investigators have since studied a plethora of options for CO2 capture from power plants which are stationary, concentrated sources of the gas and its subsequent disposal or use. Thus, CO2 capture is a common step for most of the remediation options.
In a general assessment of alternative processes for capturing CO2 from existing coal-fired power plants, Herzog et al. (1991) concluded that capture is currently technically feasible, but that the most efficient available technology will reduce energy efficiency of utility steam plants by about 30% and will increase the price of electricity by 80%, even before disposal costs are added. These results are consistent with a study by the Electric Power Research Institute (EPRI) on CO2 capture and disposal (Booras and Smelser 1991). Emerging and future electricity generation technologies have the potential to significantly reduce these costs.
Besides disposal, another potential sequestration option is to find recycle opportunities for power plant CO2 as a feedstock for industrial products or processes or as a component of alternative fuels.
For CO2 recovery, the monoethanolamine (MEA) absorption process is commonly employed and is the heart of the steam host requirement. The two commercial U.S. CO2 recovery facilities use MEA absorption technologies and produce a food- and beverage-grade product. The total industrial utilization of CO2 today in the U.S. is about 2% of the CO2 generated from power plants. However, in about 80% of the applications, as in enhanced oil recovery (EOR) and the food industry, CO2 used is rapidly returned to the atmosphere. While niches may be found for some utilization, it is unlikely that industrial use can sequester more than a minor fraction of the emitted CO2 from power plants. Use in fuels is feasible, but external energy inputs required to synthesize the fuels can be much more efficiently used to serve energy markets directly. Conversion of CO2 to microalgae is also a sequestration option; however, as in any other option, efficient recovery and delivery of the CO2 are critical.
This study discusses the environmental implications of using power-plant flue gas as a source of CO2 for microalgae cultivation and cofiring the algae with coal for electricity production.

By: K. L. Kadam (NREL)