Biomass Fuels and Energy
Biomass energy systems utilize solar energy that has been captured and stored in plant material during photosynthesis. While the overall efficiency of conversion of sunlight to stored chemical energy is low, plants have already solved the
two key problems associated with all solar energy technologies that is, how to collect the energy when it is available, and how to store it for use when the sun isn’t shining.
Plants have also very nicely dealt with the greenhouse problem since the carbon released when they use that stored energy for respiration is the same carbon they extracted in the first place during photosynthesis. That is, they get energy with no net carbon emissions.
Read more
Electricity Power Plant and Demands
Posted under Energy, Industry, Power Source
The traditional, vertically integrated utility incorporating generation, transmission, distribution, and customer energy services is in the beginning stages of what could prove to be quite revolutionary changes. The era of ever-larger central
power stations seems to have ended.
The opening of the transmission and distribution grid to independent power producers who offer cheaper, more efficient,
smaller-scale plants is well underway. Attempts to restructure the regulatory side of utilities to help create competition among generators and allow customers to choose their source of power have been initiated in a number of states, but with
mixed success.
Read more
Electric Transmission and Distribution
Posted under Industry, Power Source
While the generation side of electric power systems usually receives the most attention, the shift toward utility restructuring, along with the emergence of distributed generation systems, is causing renewed interest in the transmission and distribution (T&D) side of the business.
Below chart shows the relative capital expenditures on T&D over time compared with generation by U.S. investor-owned utilities. The most striking feature of the graph is the extraordinary period of power plant construction that lasted
from the early 1970s through the mid-1980s, driven largely by huge spending for nuclear power stations.
Read more
Gas Turbines
Posted under Energy, Industry, Power Source
The characteristics of combustion gas turbines for electricity generation are somewhat complementary to those of the steam turbine-generators just discussed.
Steam power plants tend to be large, coal-fired units that operate best with fairly fixed loads. They tend to have high capital costs, largely driven by required emission controls, and low operating costs since they so often use low-cost boiler fuels such as coal. Once they have been purchased, they are cheap to operate so they usually are run more or less continuously. In contrast, gas turbines tend to be natural-gas-fired smaller units, which adjust quickly and easily to changing loads.
Read more
Steam Power Plant
Posted under Energy, Power Source
Conventional thermal power plants can be categorized by the thermodynamic cycles they utilize when converting heat into work. Utility-scale thermal power plants are based on either the Rankine cycle, in which a working fluid is alternately vaporized and condensed, or the Brayton cycle, in which the working fluid remains a gas throughout the cycle. Most baseload thermal power plants, which operate more or less continuously, are Rankine cycle plants in which steam
is the working fluid.
Most peaking plants, which are brought on line as needed to cover the daily rise and fall of demand, are gas turbines based on the Brayton cycle. The newest generation of thermal power plants use both cycles and are called combined-cycle plants.
Read more