Energy quality can be defined as "the utility that an end user derives from a unit of energy." Today with the energy crisis looming because of exponentially increasing energy demand, the quality of engergy has become an important aspect of econmic growth. Thus better quality energy services have become the need of the hour.
The quality of energy can be determined using different methods based upon different criteria. Experts have devised different methods to evaluate this, and some of the methods are discussed below.
Evaluating Quality Of Energy – Methods
Energy Intensity Ratio (EIR) is a method devised by Carey King, the researcher mentioned above, at the University of Texas. It is loosely based upon the "Energy Return on Energy Investment" method (EROI). The primary focus of this method is to calculate the profit achieved by the consumers and not the producers.
EIR can be found for different fuels like oil, natural gas, and coal and the corresponding values for different years can be plotted on a scale. The higher the value of the EIR, the higher will be quality of energy for that particular year.
During the recessionary period of 2008, it was observed that the EIR value of different fuels had continued to fall since early 2003, and in 2008 it fell down to an all-time low resulting in a global recession. Energy rates were high, which left consumers with no choice but to pay more for gasoline and electricity, and hence the problem of the mortgage crisis emerged largely because of the liquidity crunch.
Image Credit: Jsg.utexas.edu (Please click image to enlarge.)
The Thermodynamic Approach to determine quality is complex, but effective in determining quality. It makes use of the concepts of "Emergy" and "Exergy" collectively. Thermodynamic principles are applied to the fuel under testing and methane combustion rates are determined. The Standard Enthalpy of the system along with the exergy is taken into account while calculating the methane combustion rates. The fuel that leaves minimum methane as residual is termed a quality fuel. This approach strongly emphasizes regenerative use of residual gases or masses to improve the quality of energy.
Economic or Price Based quality determination is another method. It takes into account price effectiveness of energy delivered to the customer. Price to heat equivalent ratio helps in finding out the quality of energy.
These three methods are used to detemrine quality of conventional fuels like coal, oil and gas etc.
Determining Quality of Nuclear Energy
Nuclear power plants have enabled us to relax a bit because of their efficient electricity production rate. However, when it comes to determining the quality of energy coming out of a nuclear plant, carbon debt plays an important role. From the production unit to the consumer end, the amount of green house gases released and carbon dioxide released into the air decide the quality of nuclear energy. Nuclear plants will continue to emit carbon dioxide even if all the nuclear plants across the globe are closed down today. Thus optimized use of resources and minimum carbon emission are the prerequisites of availing high quality from a Nuclear Plant. The economy is not just about the end user; it also takes into account factors like nature, environmental balance, and green house effect.
The energy sector is directly related to almost every other industrial sector, be it food production or the automobile industry, so ensuring quality energy services is very important to optimize resources and increase industrial output. More and more evaluation techniques are entering in the scene, and it is expected that very soon a standardized energy quality evaluation method will be put into the place. Energy production consumes resources and, with world standing at the verge of a great energy crisis, coal, natural gas and petroleum are not going to last forever. It becomes a moral duty to improve the quality of energy by optimizing the available resources in the best possible way to avoid any other recessionary year like 2008.
In case you run an industrial unit, make sure you conduct energy audits from time to time because in the long run, money spent today on improving quality of energy is going to give huge returns in the future. If you have short sighted vision, you can save money by avoiding energy audits and by not optimizing your energy resources, but in the long run, that will backfire because energy saved is energy generated; if you do not save today, you will end up buying tomorrow at exorbitant rates.
"Declining Energy Quality Could Be Root Cause of Current Recession, Expert Suggests," ScienceDaily, Dec. 2, 2010
"Energy Quality Factor and a New Thermodynamic Approach to Evaluate Cascade Utilization of Fossil Fuels," Refdoc.fr (Abstract)
"Energy Quality," Eoearth.org (Economic approaches to energy quality)
"Nuclear Power, the Energy Balance," Jan Willem Storm van Leeuwen, Stormsmith (PDF)