Energy systems: Environmental Impact Assessment

On this page we consider sustainable project development, the Environmental Impact Assessment process, and the environmental impacts of biofuel - fuel cell based energy systems.

Sustainable project development

Progressive approaches are required to meet growing energy needs and achieve a shift towards sustainability. These ideas are discussed on our sustainable energy needs page.

Globally, biofuels are likely to provide a major renewable energy contribution, and fuel cells offer the most efficient means of converting the limited quantities of biofuels (or fossil fuels) to electrical energy.

Fuel cells have other significant environmental advantages including low emissions, and the available information does not suggest any fundamental environmental problems.

However, initially at least, fuel cell systems will be of higher capital cost than established technologies. Our general approach to Environmental Impact Assessment (EIA) is to determine whether a fuel cell system will give a sufficient return on the investment, both in environmental and economic terms.

Integrated project management and Environmental Impact Assessment

To maximise the overall benefits of a project, the environmental assessment process should be seen as an opportunity to improve the infrastructure and technology. Thus the project should :

• Meet human needs and those of the organisation
• Develop effective technology (efficient, accessible, & affordable)
• Include systematic and inclusive Environmental Impact Assessment
• Promote financial innovation (work with real values and costs)

Environmental Impact Assessment process

The scope of the assessment

Before undertaking the assessment it is necessary to identify the purpose (compliance, improvement, investigative) and scope (system, installation, product, local, regional, or global) of the assessment, and who the assessment is for (the stakeholders).

We have designed a general assessment method which can be adapted for any situation, but our primary objective is to determine the best global environmental option and the influence of other factors.

Describe the nature of the development We are considering projects to provide energy to meet human needs. They may be in the developed or developing world; for urban, rural, or remote locations; and community or process applications. Identify environmental aspects and agree their significance Our method is designed to prioritise the significance of environmental aspects, using an inclusive process, to facilitate effective investment in the environment. There are many aspects to assess and impacts to address. The method should ensure effort for quantitative analysis and improvement actions are committed to the right areas. Assess the environmental performance The scheme performance is assessed and the resulting environmental impact evaluated under each aspect using detailed assessment methods such as resource use planning and life cycle assessment, or risk assessment, depending upon the purpose of the assessment. Environmental improvement measures The assessment will show the most significant adverse environmental impacts, and attempts should be made, in order of preference; to avoid, prevent, or mitigate these impacts using a participative approach, technical, or economic means.

Describe the nature of the development Scope of application & impacts Alternative scenarios Identify environmental aspects Agree significance Indicators & comparative data Assess environmental performance Resource use planning Life cycle assessment Risk assessment Environmental performance improvement Avoid adverse impacts Prevent adverse impacts Mitigate adverse impacts Environmental Impact Assessment Process

Establish the Best Environmental Option

Once the environmental assessment has been completed and environmental improvement measures incorporated alternative schemes should be compared. There is an increasing requirement for the Best Environmental Option (BEO) to be chosen:

• Environmentally and for the local community
• Economically and commercially considering market, financial, & legal factors

Partnerships between the various stakeholders offer a means of meeting conflicting requirements and constraints.

BIOFUEL - FUEL CELL ENERGY SYSTEMS

Environmental summary statement

Description of Need

A large increase is required in the effective use of renewable energy to meet increasing world wide energy demands, reduce the high depletion rate of valuable fossil fuel reserves, and reduce global warming. Biofuels are a major renewable energy source and fuel cells offer the most efficient means of generating electricity from biofuels.

Alternatives

These include:

• Centralised electricity generation using nuclear power: Only appropriate where a sufficient support infrastructure exists; Consequence of accidents, and management of nuclear waste are major issues
• Local electricity generation using biofuels as the fuel source, and combustion engines or fuel cells as the prime mover: Fuel cells offer more efficient utilisation of biofuels, and lower emissions, but initially at a higher cost
• Hydroelectricity and tidal: Available sites limited and adverse impacts from flooding and water use may be significant
• Wind power: Effective sites limited and varying power output requires connection to a large network
• Wave: Technical development required before it can be considered a viable alternative except at a few specific locations
• Solar: Limited energy available and high cost using current technology, dependent upon climate
• Geothermal: Mainly a source of low grade heat energy; Limited sites and difficulty of extraction

Environmental Aspects and Impacts

Environmental aspects of systems under consideration

Social inclusion

Meeting growing energy demands in the developing world
A significant positive impact identified from the assessment is the potential to meet growing energy demands and contribute to general infrastructure development in the developing world. However the technology must be accessible and affordable before this potential can be realised. Barriers to this development include the cost of the bio-digesters, fuel clean-up equipment, and fuel cell systems; and the lack of commercial availability and useful information on fuel cells.

Economic development

Risk of increased costs or loss of income
Although the costs per unit energy may be high as described above, the projects are small scale with low risk of increased costs or damage to the local infrastructure causing loss of income. Low economic risk was assigned a higher environmental significance than return on investment using our assessment method.

Resource Use Depletion of non-renewable energy sources Electrcity is the main attribute of this era. Coal, oil and natural gas have been fueling power generators, since the beginning of the industrial revolution. Economic and social reasons have forced major improvements in energy systems, as far as emissions and efficiencies are concerned. Although there has been a lot of development, fossil fuels still provide 68 % of today 's total energy supply (Fig. 1), leading to their fast depletion. There are two ways to overcome this issue: a. the energy conversion schemes should have high efficiencies, and b. renewable energy schemes must contribute a bigger part in power generation. Reduced depletion of fossil fuels is confirmed as a major positive environmental impact of FC systems.

Fig.1: Power generation (by fuel) - Source: DTI

Environmental Impacts Air pollution and air quality FC systems are relatively environmentally benign. Fig.3, illustrates the difference in emissions from conventional CHP schemes and a FC CHP. All emissions are very low except the CO2 emissions described above. Hazard to range of natural species or biodiversity The biofuel - fuel cell systems have low general impact on the natural environment, although the introduction of energy crops should be managed to avoid spread of disease or the crops overwhelming indigenous species. Other impacts The manufacturing process is manageable. Extraction and processing of nickel is the main hazard but the quantities of nickel required are low. Noise levels are low. Pathogens may be destroyed by higher temperature bio-digestion, and digested waste is less attractive to rodents and insects. Hence bio-digestion can have significant health benefits.

Fig.3: Emissions from CHP schemes

Improvement Measures

As stated above, the main adverse environmental impact is global warming from CO₂ emissions. Improvement actions include:

• Avoid CO₂ emissions by using alternative non-combustion energy sources to the greatest extent possible in the energy mix: Nuclear, Hydro, Wind, Wave, Solar, Geothermal;
• Avoid CO2 emissions by developing hydrogen fuel sources for fuel cells;
• Reduce CO₂ emissions by maximising the efficiency of the prime movers: The order of preference is high temperature fuel cells, low temperature fuel cells, combustion engines;
• Mitigate global warming impact by maximising schemes which capture methane which would otherwise be released to atmosphere. Farm slurry digester schemes have the greatest potential.