Conventional power production

Figure10.4 Primary energy savings ofacombined heat and power (CHP) system fora one-famiiy house compared with conventional power production (T)ei = 40%) and the steam gas turbine process (riel = 55%) upper lines correspond to an overall efficiency of the CHP system of 90%, lower lines to 80% [16].

Methanol, a clean burning fuel relative to conventional industrial fuels other than natural gas, can be used advantageously in stationary turbines and boilers because of its low flame luminosity and combustion temperature. Low NO emissions and virtually no sulfur or particulate emissions have been observed (83). Methanol is also considered for dual fuel (methanol plus oil or natural gas) combustion power boilers (84) as well as to fuel gas turbines in combined methanol / electric power production plants using coal gasification (85) (see Power generation). 

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. 

Today, different processes (steam reforming, autothermal reforming, partial oxidation, gasification) are available and commercially mature for hydrogen production from natural gas or coal. These processes would have to be combined with technologies for C02 capture and storage (CCS), to keep the emissions profile low. A power plant that combines electricity and hydrogen production can be more efficient than retrofitted C02 separation systems for conventional power plants. 

Pyrolysis oil (bio-oil) is produced in fast and flash pyrolysis processes and can be used for indirect co-firing for power production in conventional power plants and potentially as a high energy density intermediate for the final production of chemicals and/or transportation fuels. Gas chromatographic analysis of the liqtrid fraction of pyrolysis products from beech wood is given in Table 3.6 (Demirbas, 2007). Biocmde resrrlts from severe hydrothermal upgrading (HTU) of relatively wet biomass and potentially can be used for the production of materials, chemicals,... 

The fission reaction has been successfully applied to industrial power production here the reaction is conducted not explosively, but in such a way as to provide a steady source of energy for power generation by conventional heat engines. This method is suitable -also for large vehicles such as atomic energy submarines and atomic energy aircraft (See also Atomic Weapons and Ammunition)... 

Desalination processes may be characterized by their effluents emitted to the environment, the land and atmosphere nearby, and the sea. Desalination is highly dependent on energy, and generally uses fossil energy. All types of air pollution associated with energy production, namely, the emission of NOx, S02, volatile compounds, particulates and C02, also exist through the use of electricity produced by conventional power stations or by a dedicated power station. Using gas turbines may increase efficiency and therefore reduce pollutants. 

---