Biomass electricity from

When the purpose of the installation is to produce green electricity from biomass the scale will have to be large - estimated is 400 up to 1000 MW thermal input. This is imposed by the necessity of large-scale in ort at relative high costs. Due to the economy of scale cost-effective products can be made even with the high feedstock price and is it also economic to install extensive gas cleaning to remove all impurities. 

Energy from biomass is hardly commercially viable for any technological option at the current price levels of competing conventional alternatives in the Netherlands. Representative price levels for the production and supply of these alternatives are presented in Table 2. Due to the cunent process of liberalisation of both the electricity and the gas markets, prices are expected to drop substantially. Regarding electricity the decrease may lie in the order of 20 - 25%, whilst the gas wholesale prices may become 10-15% lower. Therefore, utilisation of renewable electricity from biomass is stimulated by financial and fiscal incentives to achieve the Dutch COj-targets. These measures should be placed in the above-mentioned framework of the Dutch policy to achieve an improvement of 10% energy supply from renewables in 2010,... 

Animal waste on a farm can also be used as biomass to produce electricity. This new technology holds great promise for disposing of mimicipal and animal wastes in a positive way. The benefits of producing electricity from biomass include ... 

On the other hand, between 2004 and 2006, total SNG production costs have been estimated to be in the range of 10-30 /GJ for capacities of 10-1000 MW, which increases by decreasing the plant size. Taking into consideration a natural gas price of 6 /GJ, the amount of subsidy required for the implementation of SNG production facilities (1.2-8.9 ct/kWh) has been estimated to be comparable with the range of financial support for producing electricity from biomass (6.0-9.7 ct/kWh), suggesting that this technology can be afforded [6, 7]. 

In the United States about 3 percent of all electricity produced comes from renewable sources of this a little more than half comes from biomass. Most biomass energy generation comes from the lumber and paper industries from their conversion of mill residues to in-house energy. Municipal solid waste also is an important fuel for electricity production approximately 16 percent ot all municipal solid waste is disposed of by combustion. Converting industrial and municipal waste into bioenergy also decreases the necessity for landfdl space. 

Most electricity from biofuels is generated by direct combustion. Wood fuels are burned in stoker boilers, and mill waste lignin is combusted in special burners. Plants are generally small, being less than 50 MW in capacity. There is considerable interest in combustion of biomass in a process called cofiring, when biomass is added to traditional fuels for electricity production. Cofiring is usually done by adding biomass to coal, but biomass also can be cofired with... 

Economics for generating electricity from biogas can be favorable. Landfill gas from municipal solid waste can supply about 4 percent of the energy consumed in the United States. In 1997, a total of 90 trillion Btus were generated by landfill gas, about 3 percent of total biomass energy consumption. 

For natural-gas-fuelled CHP plants, the same line of argumentation holds as for the stationary use of hydrogen from biomass. It is more reasonable to use natural gas directly than to convert it to hydrogen first and then to heat and electricity. High electrical efficiencies can be reached in the stationary sector by feeding natural gas to molten-carbonate fuel cells (MCFC) and solid-oxide fuel cells (SOFC). Molten-carbonate fuel cells have the added advantage of using C02 for the electrolyte (see also Chapter 13). 

To conclude, the generation of pure hydrogen from solid biomass is only reasonable if transportation fuel should be produced. But it is not reasonable to produce pure hydrogen from biomass for stationary heat and electricity generation. 

In contrast, the yield of electricity from photovoltaics (PV) is about 337 500 kWh per ha and year, even if it is assumed that the area of the PV panels cover about one-third of the total plant area. If PV electricity were converted to liquid hydrogen (LH2), stored and then converted back to electricity by a combined cycle gas turbine (CCGT, efficiency 57.5%) about 104000 kWh electricity could be generated per ha and year. This yield is still more than three times the yield of the best biomass pathway (upper end of bandwidth electricity from biogas via large gas engine). 

---