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BASICS OF ENERGY MANAGEMENT. Section A - Energy Basics. Basics of Energy Management.
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BASICS OF ENERGY MANAGEMENT Section A - Energy Basics
Basics of Energy Management These resource materials were developed by the Kentucky Pollution Prevention Center at the University of Louisville for KEEPS – Kentucky Energy Efficiency Programs for Schools – with support from the U.S. Department of Energy, and the Kentucky Department for Energy Development and Independence.
Basics of Energy Management Electricity Units • Watt (W) Electrical unit of power • Kilowatt (kW) • Unit of power equivalent to 1,000 watts of electrical demand • Kilowatt-hour (kWh) • Amount of energy consumed when 1,000 watts are used for one hour
Basics of Energy Management Electric Demand Components • Demand Period Time interval during which flow of electricity is measured (usually in 15-, 30- or 60-minute increments depending on rate structure) • Peak Demand • Highest average demand over the demand period in the billing period • Electric Load Factor (ELF) • Indicates if peak demand is high for the facility
Basics of Energy Management Electric Demand Profile
Basics of Energy Management Natural Gas Units • Btu: British thermal unit • MMBtu: Million British thermal unit • Btu/hr: British thermal unit per hour • CCF: Hundred cubic feet 10 CCF = 1 MMBtu • Dth: Dekatherm 1 dth = 1 MMBtu or ~10 CCF
Horsepower (hp) = 745.6 watts Conversion – Apples to Apples • Basics of Energy Management • Motor hp = 2,545 Btu/hr • Boiler hp = 33,475 Btu/hr • Cooling ton = 12,000 Btu/hr • 1 kilowatt = 3,412.3 Btu/hr
Efficiency Work done divided by work put into the system Efficiency Terms work out work in = % • Basics of Energy Management • Efficacy • Measure of performance using units • lumens/watt for lighting • kW/ton for chillers
Coefficient of Performance (COP) Measurement of how efficiently a heating or cooling system operates at a single outdoor temperature condition Temperature condition for heat pumps = 47°F HVAC Efficiency – COP • Methods to calculate COP Heat PumpChiller Btu of heat produced (47◦F) • Btu of electricity used (47◦F) 3.516 kW/ton • Basics of Energy Management
HVAC Efficiency – EER Btu/hr cooling at 95°F watts used at 95°F • Method to calculate EER • Basics of Energy Management • Energy Efficiency Ratio (EER) • Measurement of how efficiently a cooling system operates when the outdoor temperature is at a specific level (95°F) • Commonly used when referring to: • air conditioners (window, unitary) • heat pumps (window, unitary, water-source, geothermal)
Conversion - Apples to Apples Btu of cooling produced Wh of electricity used EER = Energy or heat output (total) Energy or heat input (external) COP = EER 3,412 Btu/Wh COP = • Basics of Energy Management
HVAC Efficiency – SEER • Method to calculate SEER seasonal Btu of cooling seasonal watt-hours used • Basics of Energy Management • Seasonal Energy Efficiency Ratio (SEER) • Measurement of how efficiently a residential central cooling system operates over an entire cooling season • air conditioner or heat pump • Not to be confused with EER • Split cooling system SEER must be greater than 13, effective 2006
HVAC Efficiency – HSPF • Method to calculate HSPF Btu of heat produced over heating season watt-hours of electricity used over heating season • Basics of Energy Management • Heating Seasonal Performance Factor (HSPF) • Measurement of how efficiently all residential and some commercial heat pumps operate in their heating mode over an entire normal heating season
HVAC Efficiency – AFUE • Method to calculate AFUE Btu of heat produced over heating season Btu of natural gas used over heating season • Basics of Energy Management • Annual Fuel Utilization Efficiency (AFUE) • Measurement of how efficiently a gas furnace or boiler operates over an entire heating season • Percentage of energy consumed by system that is actually converted to useful heat • AFUE for most gas furnaces must be at least 78%
Energy Accounting Terms • Basics of Energy Management • Energy Use Index (EUI): Btu/ft2/year • Use when tracking energy savings • Energy Cost Index (ECI): $/ft2/year • Use when comparing within your district • must be a small district with single utility provider
1 lb of coal burned produces 1 to 1.25 kWh Energy and the Environment • Basics of Energy Management • T12 (34W) upgrade to Super-T8 (32W) for 10 fixtures with four lamps per fixture *100 lb/yr of coal not burned*
Electric Units – kW, kWh, peak demand, ELF Review of Energy Basics • Basics of Energy Management • Natural Gas Units – CCF, MMBtu, dth • HVAC Efficiency – COP, EER, SEER, HSPF, AFUE • Energy Accounting – EUI and ECI • Energy and the Environment • 1 lb coal burned produces about 1 to 1.25 kWh