Electricity generation fuel cost

When electricity is bought from centralized power generation companies, the price tends to be more stable than fuel costs, since power generation companies tend to negotiate long-term contracts for fuel supply. 

Not all of the gas is wasted. About 300 MW of electricity is generated from landfills. A variety of electric generation systems have been employed by a small number of developers. Most projects use simple technology and are small (2—10 MW). However, an EPRI study has estimated that landfill gas resources in the United States could support 6,000 MW of generation if utilized in 2-MW-sized carbonate fuel cells. Constmction on the world s first utihty-scale direct carbonate fuel cell demonstration was begun in California. If successful, EPRI estimates that precommercial 3-MW plants based on this design could become available by the end of this decade at an installed cost of 17,000/kW. 

In electrical power stations a new measure of the performance is the amount of CO2 produced per unit of electricity generated, i.e. A = kg(C02)/kWh this quantity can be non-dimensionalised by writing A = A( 16/44)(LCV) where (16/44) is the mass ratio of fuel to CO2 for methane and (LCV) in its lower heating value. However, presenting the plant s green performance in terms of A directly allows the cost of any tax on the carbon dioxide to be added to the untaxed cost of electricity production most easily. 

Despite the fact that OTEC systems have no fuel costs and can produce useful by-products, the initial high cost of building such power plants (up to 5,000 per kilowatt) currently makes OTEC generated electricity up to five times more expensive than conventional alternatives. As such, at the present time OTEC systems are largely restricted to experimental and demonstration units. One of the major facilities for OTEC research is the Natural Energy Laboratory of Hawaii Authority at Keahole Point on the island of Hawaii. An experimental OTEC facility located there has had a maximum net power production of 100 kilowatts, at the same time producing 5 gallons per minute of desalinated water. 

The gas turbine is widely used by electrical supply authorities for peak lopping and standby generation. Additionally, it is often employed for base-load operation when the fuel costs are low. 

Thermal power plant is more commonly associated with very large central power stations. The capital cost for thermal power plant, in terms of cost per installed kilowatt of electrical generating capacity, rises sharply for outputs of less than some 15 MW. It is for this reason that thermal power plant is not usually considered for industrial applications unless it is the combined cycle or combined heat and power modes. However, for cases where the fuel is of very low cost (for example, a waste product from a process such as wood waste), then the thermal power plant, depending on output, can offer an excellent choice, as its higher initial capital cost can be offset against lower running costs. This section introduces the thermal power cycle for electrical generation only. 

Very large, modem WT boilers with sophisticated heat-recovery auxiliaries may attain efficiencies approaching 88 to 90%. However, the overall efficiency of a fossil fuel utility power generation plant system falls to only 32 to 38% when the efficiency of electricity generation and condenser cooling is included. Nevertheless, it only requires 10% more in fuel costs to operate a boiler at 1,250 psig than... 

Steam costs vary with the price of fuel and electricity. If steam is only generated at low pressure and not used for power generation in steam turbines, then the cost can be estimated from fuel costs assuming an efficiency of generation and distribution losses. The efficiency of... 

Sims, R.E.H. Rogner, H.H. Gregory K. Carbon emission and mitigation cost comparisons between fossil fuel, nuclear and renewable energy resources for electricity generation. Energy Policy 2003, 31,1315-1326. 

Power systems that run on compressed gases such as propane, methane, or hydrogen are problematical. Range may be limited since distribution systems are not in place and each station pump could cost 30,000. So-called synthetic fuels could be used directly in engines or to generate electricity from fuel cells for electric motors. Other combustion engines such as the sterling motor may also become options. 

A major cost in the operation of a dryer is in heating the air or gas. Frequently, the hot gases are produced by combustion of a fuel gas or atomised liquid, and considerable economy may be effected by using a combined heat and power system in which the hot gases are first passed through a turbine connected to an electrical generator. 

---