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Fall 2009 Workshop Level 1 Energy Audits - Energy Use Analysis - - Walk Through Analysis - Mr. Matt O’Brien, AIA, LEED AP. November 17, 2009. Agendas and Focus. Program Development. Establish Utility Baseline. Today’s Focus (Matt O’Brien). Facility Audits (Existing Conditions).
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Fall 2009 Workshop Level 1 Energy Audits - Energy Use Analysis - - Walk Through Analysis - Mr. Matt O’Brien, AIA, LEED AP November 17, 2009
Agendas and Focus Program Development Establish Utility Baseline Today’s Focus (Matt O’Brien) Facility Audits (Existing Conditions) Develop Energy Conservation Measures (ECM) Behavior Management Low Cost/No Cost System Intervention System Design Implementation (Individualized School Plan) Implementation (Individualized School Plan) Implementation (Individualized School Plan) Evaluate Results Evaluate Results Evaluate Results Reinvest Savings Reinvest Savings
Definitions: PEA’s, DES’s, SEP’s & M&V’s PEA = Preliminary Energy Audit (use “New” ECM form) DES = Detailed Energy Survey (implies modeling) SEP = Strategic Energy Plan (and Water Plan) SEP M & v = Measurement & verification m & V = measurement & Verification
Step 1 of the Strategic Energy Plan:PEA’s (Data Collection) The Preliminary Energy Audit involves collecting data about the building from construction and maintenance records and from a walk-thru of the building.
The results from an energy audit show you: 1. How efficiently your building is operating
The results from an energy audit show you: How efficiently your building is operating 2. How you can increase efficiency using low cost or no cost changes in operation
The results from an energy audit show you: 1. How efficiently your building is operating 2. How you can increase efficiency using low cost or no cost changes in operation 3. How, with a capital investment, you can increase efficiency and reliability, and decrease maintenance costs
The Energy Utilization Index (EUI) +If your building has utility meters, you can identify the least efficient buildings by calculating the EUI for each metered building. + Buildings with a high EUI are probably wasting energy and money, and they are the best candidates for an energy “tune-up”.
How do I calculate the EUI for my building? Since: 1 kW-hr = 3,412 BTUs (Electric Bill) and 1 Therm = 100,000 BTUs (Gas Bill) and The building = 63,609 square feet then
How do I calculate the EUI for my building? Electrical Energy consumption: 1/1/08 to 12/31/08: 718,613 kW-hr. Natural Gas consumption: 1/1/08 t0 12/31/08: 10,819 therms. Based on the two values, the energy utilization index (EUI) and the energy cost index (ECI) are: 55.56 kBTU/SF/YR and 1.09 $/kBTU/SF/YR
EUI & ECI Real Examples Section 1.5 Building Energy and Cost Indices: January 1, 2008 through December 31, 2008 is: 760,500 kW-h. 29,656 therms. EUI = 105 kBTU/SF/YR and ECI = 1.72 $/kBTU/SF/YRrespectively. 4,119,120kW-h. 45,269 therms. EUI = 140 kBTU/SF/YR and ECI = 2.00 $/kBTU/SF/YRrespectively. 332,820 kW-h. 3,157 therms. EUI = 123kBTU/SF/YR and ECI = 2.30 $/kBTU/SF/YRrespectively. (The facility’s energy utilization index is on the high side the reason may be the presence of two huge computer laboratories)
What if buildings are not individually metered ? + Not having individual meters makes the task of prioritizing your energy “tune-up” program difficult. + However, larger, older buildings with central air conditioning and central heating are probably the least energy efficient and should be placed at the top of the priority list. + Sub-Metering devices
The “HOBO” Option Guilford County & GTCC In-House Electricians Aiding Installation of CT DataLoggers for M & V Study
Preliminary Energy Audit Findings Top Ten Low-Cost and No Cost Items 1. High or Low thermostat settings 2. Lights left “on” in unoccupied rooms 3. Dripping hot water faucets 4. Windows open when HVAC system is “on” 5. No weather stripping around doors 6. No caulking around windows 7. Heating boilers left idling during warm weather 8. Dirty coils in HVAC equipment 9. Clogged filters in HVAC equipment 10. Incandescent light bulbs
CERT’s ECM Tally Sheet-Top Ten (Summer 2008) Note: All 40 buildings were candidates for Performance Contracting. (We were unable to obtain energy bills in most cases) HITSENERGY CONSERVATION MEASURE 35 Occupancy sensors should be installed. 21 Replace existing T-12’s with T-8’s and magnetic ballasts. 18 Remove lighting from vending machines or install vending misers. 17 Install 1.6 gpf water closets and .5 gpf urinals and low flow faucets in rest rooms. 13 Economizer needed in the building. 8 Provide optimum stop-start system for the HVAC system. 8 24/7 exhaust fans, ventilation & water heaters to be put on timer & be OFF overnight. 7 Exit lights should be replaced with LED. 7 Chiller approach should be set to 10°F – It is currently about 4.8°F. 6 Install programmable T-stats in all zones with set-back capabilities.
Step 2 of the Strategic Energy Plan:Evaluate Results & Develop Plan Once no cost and low cost opportunities have been identified, then what? 1. Leadership team awareness and support 2. Monitor progress by installing meters and/or sub-meters. 3. Education program for occupants and maintenance staff. 4. Make repairs and publicize energy-use reductions on a quarterly basis.
Step 3 of the Strategic Energy Plan:DES’s (Quantify Energy Savings) The Detailed Energy Survey identifies and quantifies capital investment opportunities that will increase HVAC system and lighting system efficiency and reliability, and will decrease maintenance costs. The Detailed Energy Audit is conducted by a professional engineer who calculates utility savings, engineering design costs, construction costs, and payback.
Energy Simulations: Consumption Fig.3: 2008 Electric Energy Consumption
Energy Simulations: Demand Fig. 4: 2008 Electric Power Demand
Detailed Energy Audit Top SIX Energy Investment Opportunities 1. Lighting replacement, occupancy sensors, and day-lighting controls. 2. Installing state-of-the-art HVAC controls 3. Installing variable speed drives on pumps and fans. 4. Updating outside air economizer controls. 5. Installing energy recovery units. 6. Replacing old, inefficient HVAC boilers and chillers,
Step 5 of the Strategic Energy Plan:Capital Project Implementation (Steps 4 and 6 are M&V’s) Selecting capital projects by choosing only projects with short paybacks, like relamping. Example: Replacing T12, 34 watt fluorescent lamps with T8, 25 watt lamps and electronic ballast: Estimated Savings $ 13,981 / year Estimated Cost: $ 39,597 Simple payback period: 2.8 years
Step 5 of the Energy Management Program: Capital Project Implementation Accepting a longer payback and funding more Projects, like motor replacement. Example: Replace the 75 hp Motor with Premium Energy Efficient Motor • Estimated Savings: $ 905 / year • Estimated Cost: $ 4,436 • Simple payback period: 4.9 years • It is assumed that the motor is operated 6000 hour/year.
Means of Capital Project Funding • Raise construction funds (bonds, gifts) • Hire an architect and engineer to prepare plans • Bid the project • Monitor Construction • Commission the project • Performance Contracting • Select a performance contractor • Sign the contract
Steps 4 & 6 of the Strategic Energy Plan: M & V (Measurement & Verification) Based on a year of actual operation, did the retrofit project reduce energy costs as predicted? Attend Dr. Rojeski’s presentation tomorrow.
Data Collection Measure Results Evaluate Results Implement Plan Develop Plan 1. Data Collection – PEA 2. Evaluate Results/Develop Plan 3. Quantify Energy Savings – DES 4. Establish Baseline - M & v 5. Implement Plan 6. Verify/Validate - m & V Review and Questions