Learning Center Articles
How are companies billed for their energy usage (electric and gas)? When companies buy gas they are charged for each Cubic Feet. Similarly, when companies buy electricity they are charged by the kilowatt-hour (kWh). Companies are billed monthly by two separate companies for their electricity usage. The first bill is from the Electrical Supply Company and the second bill is from an Electrical Distribution Company. The Electric Generation Company actually produces the electricity making it distribution ready. The Electrical Transmission Distribution Company provides the means to get the electricity from the supplier or generator to the customer. The Electric Supply Company charges Kilowatt- hour consumed. Whereas, the Electrical Distribution Company charges per Kilowatt, Kilowatt- hour and highest demand charge. The rates are determined by the location of the company, how much the company uses per month, time of use, and possibly what time of year it is. Company A (The investigators place of employment) used 1,343,333 KW-Hr for the month of March (2010) at a rate 1.8667 per KW-Hr equating to a monthly bill of $25,075 from the Electric Distribution Company. Company A is also charged 7.937 cents per KW-Hr equating to $106,628 by the Electrical Supply Company. Company A’s electric bill for the year would equate to approximately $1,580,436. With rising energy prices it becomes more imperative to consume less electricity. Reducing consumption lower Company A’s electric bill by 15%, which would save a whopping $237,065 per year! By reducing electrical energy consumption also reduce the amount of CO2 emissions needed to generate that additional electricity.
What does it mean to be electrically efficient? An efficient system is performing or functioning in the best possible manner with the least waste of time and effort; having and using requisite knowledge, skill, and industry; competent; capable: a reliable, efficient secretary. Electrical Efficiency is calculated by:
Electrical efficiency is simply using less energy to provide the same level of energy service. An example would be a fluorescent light versus an incandescent light; maintaining the same level of illumination. A 13 watt fluorescent light bulb outputs the same amount of visible light as a 60 watt incandescent bulb, so the reader is getting more light for less energy and less money. Efficient energy use is achieved primarily by means of a more efficient technology or process rather than by changes in individual behaviors. Efficiency should not be confused with effectiveness: a system that wastes most of its input power, but produces exactly what it is meant to is effective but not efficient. The term "efficiency" only makes sense in reference to the wanted effect. A light bulb might have 5% efficiency at emitting light yet still be 95% efficient at heating a room. (In practice it is nearly 100% efficient at heating a room because the light energy will also be converted to heat eventually. Consider an electronic amplifier that delivers 10 watts of power to its load (for example a mid range speaker), while drawing 20 watts of power from a power source is 50% efficient as shown below:
It is important to understand how to derive efficiency when projecting a cost savings. In addition, understanding how to calculate watts, which equals power, is necessary.
A watt versus watt-hours can be difficult to understand. A watt-hour is a confusing term because it is not a unit of power, like the watt. A Watt is the rate of electricity used at that instant and Watt-hours is the total energy used over time. A common misconception is that if the reader increases the voltage the overall power will decrease. The electric company charges the reader for watt-hours, not volts, to which the wattage remains the same. To figure Watts use the formulas:
Volts x Amps = Watts
Amps^2 x Ohms = Watts
A devices Amperage and Wattage will be directly proportional if the source voltage remains the same. Figure 1 shows that if a device’s Amps increase by a factor of 10 that the Watts will also increase by a factor of 10. One could hypothesize further by stating that the bill would be 10 times larger as well.
Analysis - an examination of facts and data to provide a basis for effective decisions.
Data - are simply representations of facts that come from some type of measurement process.
Efficient - performing or functioning in the best possible manner with the least waste of time and effort; having and using requisite knowledge, skill, and industry; competent; capable: a reliable, efficient secretary.
Information - is derived from the analysis of data and measurements and expressed in the context of a business or organization.
Measurement - is the act of quantifying the performance dimensions of products, services, processes, and other business activities.
Measures and indicators - refer to the numerical results obtained from measurement.
Power factor - The power factor of an AC electric power system is defined as the ratio of the real power flowing to the load to the apparent power, and is a dimensionless number between 0 and 1 (frequently expressed as a percentage, e.g. 0.5 pf = 50% pf).
Luminescence - is the photo metric measure of luminous intensity per unit area of light traveling in a given direction.
Real Power – Real power is the capacity of the circuit for performing work in a particular time.
Reactive Power – The portion of power flow remaining after being averaged over a complete AC waveform.
Apparent Power - Apparent power is a measure of alternating current power that is computed by multiplying the root-mean-square current by the root-mean-square voltage.