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Mwawughanga 410 Report 17 emit greenhouse gases (CO 2 ) due to the decomposition of vegetation, but the scale of these emissions is highly variable and more research on a case-by-case basis is needed (Canhydropower, 2003). The emissions depend on the area and amount of vegetation before impounding. Sources such as solar and wind power emit small amounts of CO 2 . A comparison of gaseous emissions from different power sources are given in Table 3. TABLE 3: Comparison of emissions from different power sources (Reed and Renner, 1995) Emissions (kg/MWh) Geothermal Coal Petroleum Methane Hydro Sulphur dioxide (SO 2 ) 0.03 9.23 1.92 0 0 Oxides of nitrogen (NO x ) 0 3.66 1.75 1.93 0 Carbon dioxide (CO 2 ) 0.48 990 839 540 0.45 Geothermal power plants emit only a small fraction of sulphur compared with fossil fuels. The source is hydrogen sulphide (H 2 S), commonly found in geothermal steam, which is oxidized to SO 2 in air. Geothermal power and hydropower stations emit no NO x . The small amount of ammonia found in geothermal sources is oxidized to harmless nitrogen and water. CO 2 emissions range from zero in binary plants, to 0.48 kg/MWh of electricity produced using flash technology. Hydropower plant emissions range from 0 to 0.45 kg/MWh, while solar and wind power plants emit 0.02–0.29 kg/MWh and 0–0.1 kg/MWh, respectively (after Hunt, 2001). 2.2.3 Land requirement in relation to other energy sources Land needs for different types of power projects depend on size of the developments and technology used, among others. All the developments need land for powerhouses and associated buildings. For geothermal power, land is disturbed by well-pad preparation, road construction and pipelines (fuel acquisition), in addition to office buildings. However, this is minimal. The average geothermal plant occupies about 400 m 2 per gigawatt hour for 30 years (Reed and Renner, 1995). Land requirements for oil and gas are similar to those for geothermal power. However, nuclear and coal power plants require larger areas for the mining space and safety buffer zones. Hydropower, in contrast, can occupy large areas where reservoirs are used for water storage, thus displacing people in populated areas. This has partly led to campaigns against such development. The construction of medium-sized plants of the run-of-the-river type without large reservoirs does not create such problems. However, most of the plants are located in remote, uninhabited areas and positive impacts outweigh negative ones. 2.3 Contributions of geothermal power and hydropower in Iceland and Kenya Hydropower and geothermal power contribute the greatest bulk of electricity in Kenya and Iceland. In Iceland, hydropower contributes 84.1%, geothermal power 15.8%, while only 0.1% comes from fossil fuel (Fridleifsson, 2000b). In Kenya, 74.2% of the electricity comes from hydropower and about 8% from geothermal; while the rest comes from wind, diesel, and thermal (KenGen, 2003). Thus, their importance in the economic and social development cannot be underestimated. There is still a great potential of geothermal resources in Kenya. However, 70% of the Kenyan energy needs come from burning of biomass (Kenya Energy profile, 2003). This leads to degradation of the environment through deforestation, consequent soil erosion and degradation, biodiversity loss and undesirable gas emissions, which cause respiratory problems in the users.
Report 17 411 Mwawughanga 3. ENVIRONMENTAL LEGISLATION AND IMPACT ASSESSMENT Environmental Impact Assessment (EIA) is a fundamental development component in most countries today, and even in countries that do not have environmental regulations, multilateral financial institutions have made EIA mandatory before lending. Thus, environmental legislation has become a crucial component, alongside finances and other factors in development of projects. Environmental regulations of different countries are remarkably similar. Most require an environmental analysis of proposed power projects, as well as having specific regulations defining quantities of pollutants that may be emitted to the atmosphere or discharged to land and water. The analysis usually comes with a report referred to variously as Environmental Assessment (EA), Environmental Impact Assessment (EIA), Environmental Impact Statement (EIS), or Environmental Impact Report (EIR) (Hietter, 1995). Major variations exist in terms of agencies involved and time required for the process to be completed. The purpose of the EIA is to ensure that potential impacts are foreseen and addressed at the earliest possible opportunity. It also provides information that helps in proper planning and should provide an opportunity for stakeholder involvement. 3.1 Environmental legislation of Iceland and its role in power development projects In Iceland, there are a number of laws addressing geothermal development (Andrésdóttir et al., 2003). These include the following: 1. Planning and Building Act no. 73/1997. The Act states that in order to obtain development permits, substantial development projects shall be in accordance with development plans and decisions on environmental impact assessment (EIA). 2. Research and Use of Underground Resources Act no. 57/1998. The Act requires the developer to apply for an exploration permit before starting further research and drilling of exploration wells, and utilisation permit before constructing a power plant. 3. Nature Conservation Act no. 44/1999. According to the Act, certain landscapes and habitats enjoy special protection. Amongst these are hot springs and other geothermal sources, surface geothermal deposits, volcanic craters and lava fields, all being frequent features of high- temperature geothermal areas. 4. The Energy Act no. 65/2003. The Act requires that developers planning to exploit geothermal resources for producing more than 1 MW electric power must apply for operation permits. The Environmental Impact Assessment Act no. 106/2000 deals with all projects that may have impact on the environment in Iceland and went into effect in June 2000. Legislation on environmental impact assessment was first passed in Iceland in 1993. The main aim of the new Act is to ensure that environmental impacts of projects likely to have significant effects on the environment, natural resources or community are assessed before any permission is given for implementation. High priority is given to public review, unlike the earlier Act, and to cooperation among different groups and the developer. The main changes from the earlier Act are that responsibility for the screening process has been transferred from the Ministry of Environment to the Planning Agency, and a new formal scoping process has been introduced whereby the developer prepares and submits an EIA programme for the proposed project to the Planning Agency as early in the procedure as possible (Thors, 2000). Thus, the Planning Agency (Skipulagsstofnun) monitors the application of law and regulations on planning, building, and EIA. The Minister for Environment has supreme control of planning and building under the Planning and EIA regulations. The assessment must be part of a planning process. A regulation supplementing the Environment Act lists project categories requiring an EIA. Other projects that may or may not be subject to an EIA depending on their magnitude are listed in Appendix 2 of the regulations. This includes drilling
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