Energy Technology – Fuel Cells and Biomass
Fuel cells are energy converters that obtain electrical energy from hydrogen or hydrogen-containing hydrocarbon. On the other hand, biomass is a regenerative energy carrier-fuel obtained from renewable resources.
The fuel cell is the big sister of the alkali cell (domestic type of battery), that is, an electrochemical energy converter. The main difference between dry cell batteries and rechargeable (storage) batteries on one side and fuel cells on the other is as follows: While household batteries and large storage batteries store electrical energy when charged, which is given off again later on, fuel cells—like combustion engines-are supplied constantly with fuel.
For that purpose, hydrogen or a hydrocarbon-containing gas such as methane, are used. In the first case, the waste gas is water, and in the second case, it is carbon dioxide. This process generates distinctly less waste heat than combustion engines, hence it is referred to as a “cold burn.” Although this efficient technology is exacting—requiring extreme precision—and not yet sufficiently refined for all applications, its potential is impressive.
The spectrum of possible applications extends from decentralized, small power plants to vehicle propulsion to micro-fuel cells for notebook computers and camping cookware equipment.
Biomass utilization
The very first energy carrier was wood. The use of fire can even be considered the starting point of human history as such. Especially since the start of industrialization, fossil fuels such as coal, crude oil, and natural gas have increasingly displaced wood. However, from an ecological point of view, wood has a distinct advantage: along with straw and other so-called biomass components, wood releases only as much climatically harmful carbon dioxide (CO2) as plants have removed from the atmosphere during their growth period.
Within this context, burning biomass is “CO2-neutral” Meanwhile, in view of rising crude-oil prices, the cultivation of energy plants has become an interesting economic question. Fuel for wood-chip or pellet heating has a similar cost factor as heating oil, and in a few years the costs related to such wood fuels will presumably be distinctly less. Additionally, there are still problems with biomass burning due to a high micro-dust component.
It is also feared that competition will arise between the cultivation of food products and fuel plants, which can presumably only be defused by intelligent and sound agricultural politics.
ALTERNATIVE ENERGY PRODUCTION TECHNOLOGIES
The scarcer and more expensive fossil fuels become, and the faster global warming occurs, the more alternative energy technologies are going to be used. Wind generators, solar parks, and high-pressure hydropower plants are being further refined and deployed on a larger scale than ever before.
The use of tidal currents to drive turbines has so far only been used in prototype form. Solar cells are also relatively widely used, yet the amount of solar power being utilized today is still far behind that of water or wind.
BASICS
BIOMASS During photosynthesis, plants (along with some bacteria) convert carbon dioxide(CO2) and water (H2O) into biomass (for example, hydro-carbons, Cx(H20)y) and gaseous oxygen O2). Here, sunlight serves as an energy source.
During combustion (or digestion), this energy is released again. Therefore biomass is, in effect, stored solar energy.