Energy Savings Audit

Transcription

1 Energy Savings Audit PREPARED FOR Steve Bennett Eileen Horn City of Lawrence ASSESSMENT SITE City of Lawrence Arts Center 940 new Hampshire St. Lawrence, KS ASSESSMENT PERFORMED BY P1 Group Inc W 108th St Lenexa, KS ASSESSMENT DATES 03/09/ /19/2012 REPORT ID

2 Executive Summary This Building Performance Assessment is designed to help key stakeholders understand the building s operation in the following areas: Current energy usage and actions you can take to reduce energy waste Financial analysis of proposed conservation measures Comfort and ventilation issues related to mechanical system operations Verification of schedules for the operation of temperature and lighting control systems The following summarized identified energy savings measures by category. Reference detailed Energy Savings Opportunities for associated economics and savings: Temperature Increase the unoccupied heating and cooling temperature setback range Calibrate local terminal devices and thermostat(s) to reduce temperature variation Relocate local thermostat(s) to reduce temperature variation Program the central BMS to monitor and control temperature scheduling Balance air flow within duct system to reduce temperature variation Lower the occupied heating set point Raise the occupied cooling set point Related ECM s Retro-Commissioning, Test & Balance, Controls Upgrade Relative Humidity Improve ventilation control Consider humidification and dehumidification systems to maintain constant moisture levels Excessive humidity swings were witnessed over the evaluation period. Improper humidity control can be a result of excessive ventilation. If humidity is not properly controlled, damage to exhibit pieces can result. Related ECM s Retro-Commissioning, Test & Balance, Controls Upgrade Carbon Dioxide Verify outside air dampers are not stuck open or leaky Reduce the amount of outside air ventilation Install demand control ventilation Regulate ventilation to maintain between 700 and 1000 ppm of CO2 in occupied spaces Related ECM s Retro-Commissioning, Test & Balance, Controls Upgrade Lighting Replace inefficient lamps with new high efficiency lamps Install occupancy sensors for individual zones o Recommended for backstage and non-exhibit areas Install daylight controls on the perimeter o Repair roll-out sun shade mechanisms o Evaluate and adjust required lighting levels Reduce after hours use through coordination with the cleaning crews 2

3 Related ECM s Partial Lighting Upgrade HVAC Controls Upgrade Controls upgrade is necessary to provide improved temperature, scheduling, terminal device, and ventilation control of building HVAC systems. Updated control technologies can provide integration with user end devices (i.e. Dashboards) to provide up to date building energy use and system operating status. Related ECM s Retro-Commissioning, Test & Balance, Controls Upgrade Equipment Upgrade Heating equipment is becoming aged and lacks efficiency standards of current technologies. We recommend replacing one boiler with a more efficient condensing hot water boiler to provide more economical operation at part loads. Related ECM s Equipment Upgrades Retro-Commissioning and Test & Balance Retro-Commissioning provides a comprehensive HVAC system analysis. This process identifies current building operating requirements, compares original system design, and recognizes efficient and practical measures for maintaining building environmental stability and efficiency. Implementing Retro- Commissioning can be beneficial to understand underlying deficiencies and limitations of current building HVAC systems. Additionally consider balancing system air and water flows to meet current zone and equipment requirements. Typical costs can range from $35,000 - $45,000 for this size building for Investigation & Analysis with Corrective Action Planning, and Test & Balance. 3

4 How to Achieve Energy and Cost Savings After evaluating the building s actual performance we propose the following actions for lowering energy use and costs: Energy Savings Opportunities: Estimated Savings Recommended Energy Conservation Measures Electricity (kwh) Fuel (therms) Total Yearly Savings Estimated Cost Simple Payback w/o Rebate O&M Savings Simple Payback w/ O&M Partial Lighting Upgrade Partial Lighting Upgrade $32,000 $10,000 SubTotal 41,857 0 $3,552 $32, Years $10, Year Equipment Upgrades Boiler Upgrade $60,000 $ SubTotal 0 6,600 $4,534 $60, Years $ Year Retro-Commissioning, Test & Balance, Controls Upgrade Retro-Commissioning and Test & Balance $40,000 $ Occupied/Unoccupied Temperature Control $30,000 $ Ventilation on Demand $ SubTotal 107,655 1,784 $10,360 $70, Years $0 6.6 Year Sum Total* 149,512 8,384 $18,445 $162, Years $10, Year *The sum total does not reflect the order of implementation of the proposed energy conservation measures and therefore does not reflect any interactive effects this sequence would have on realizing the full savings potential. 4

5 How You Use Energy Today This page uses the information gathered on your building during the assessment to benchmark your building s performance versus peer buildings of the same type and size across the country. The comparison uses ENERGY STAR and the Department of Energy s Commercial Buildings Energy Consumption Survey database (CBECS). Energy Usage Index Energy Consumption (kbtu / ft 2 per year) Explanation The Energy Usage Index is your building s estimated Energy Consumption (kbtu / ft 2 ) in comparison to a range of peer buildings. Current Annual Energy Consumption Findings The Current Annual Energy Consumption pie chart shows the estimated consumption of each typical energy end use for your building. 5

6 Energy Savings Analysis The Energy Savings Analysis for your building is outlined on this page. The analysis is based on a sophisticated set of energy modeling algorithms and actual building performance data. It shows the current usage and potential energy and cost savings opportunities from the proposed changes highlighted. Annual Energy Comparison Explanation The Annual Energy Comparison chart compares your current energy use against energy use after implementing the proposed energy conservation measures. Energy savings are for a typical weather year. Projected Energy Cost Explanation The Projected Energy Cost chart compares the current monthly costs against projected monthly costs after implementing the proposed energy conservation measures. Projected savings are for a typical weather year. Return on Investment Cost to Implement $162,000 O&M Savings $10,000 Payback Period 5.7 Years Est. Annual Savings $18,445 Summary The Return on Investment information gives a high-level view of the costs associated with the proposed energy conservation measures, the resulting savings, and a simple payback estimate. The estimated annual savings represents a 21% reduction in your annual energy cost. 6

7 ENERGY STAR and Sustainability The ENERGY STAR Energy Performance Rating is a great way to benchmark a building against peer buildings. Other metrics included on this page are the carbon footprint of the building (using EPA s utility emission data), the estimated energy reduction of the recommended energy conservation measures, and the equivalent carbon footprint reduction. The Arts Center building is not eligible for an ENERGY STAR score. The facility usage and space type is has not yet been evaluated by the EPA to determine an accurate comparison to Industry Averages. However, the building EUI and Carbon Emissions can be evaluated and projected below. Carbon Emissions Benchmark Summary The carbon footprint of a building measures the building s impact on the environment through its greenhouse gas emissions. This chart shows your building s current carbon footprint and the potential reduction associated with our recommendations. Equivalent Carbon Footprint Reduction Estimated Annual Savings 47 acres of trees 33 cars 149,512 kwh 8,384 therms Implementing the proposed energy conservation measures will reduce greenhouse gas emissions by 375 thousand pounds of carbon dioxide per year, equivalent to removing 33 cars from the road or reforesting 47 acres of trees. The Estimated Annual Savings from the reduction in energy usage is based on the energy conservation opportunities proposed in this report. 7

8 Energy Findings Proposed Energy Conservation Measures Building Performance Your Energy Usage Index ranks your building as a high energy user. We Recommend The recommended energy conservation measures in this report can generate a yearly energy reduction of 149,512 kwh and 8,384 therms. This will reduce your carbon footprint by 375 thousand pounds of carbon dioxide. View all of the conservation measures on Page 6. The Bottom Line We recommend investing $162,000 on select energy savings measures for a payback of 5.7 years and an estimated energy savings of $18,445 per year. This is a 21% reduction in overall utility cost. Comfort & Ventilation What we Tested and Found Temperature (T) 2 of 10 spaces measured had excessive deviations from the optimum comfort range. Relative Humidity (RH) 10 of 10 spaces measured had excessive deviations from the optimum comfort range. Carbon Dioxide (CO2) 1 space(s) had elevated carbon dioxide levels 6 space(s) had low carbon dioxide levels Areas of Interest Preschool (RH,CO2) Theater (RH,CO2) S Art (RH,CO2) S Dance (RH,CO2) Office (RH,CO2) Lobby (RH,T) Cafe (RH) Ceramic (RH) N Art (RH,T) Print Rm (RH,CO2) 8

9 Outdoor Conditions Outdoor conditions recorded during the test period are included as part of this report. The outdoor data included in this report was recorded at: Lawrence, KS Outdoor Temperature Test Period Avg: 3/9/12 3/19/12 Heating Degree Days Cooling Degree Days 62 ºF 6 3 Outdoor Temperature and Dewpoint A major factor in the total cost of heating and cooling a building is the heat lost (during heating season) or gained (during cooling season) due to the difference between indoor and outdoor temperatures. The amount of energy consumed to compensate for the difference between outdoor temperature and the desired indoor temperature is driven by three primary factors: Heat lost or gained due to conduction through walls, ceilings, and windows. Energy required to heat, cool, and dehumidify outside air entering the building, either through infiltration or mechanical ventilation. Heat gain due to solar load. This chart shows the outdoor temperature and relative humidity during the test period at the test location. More aggressive temperature setbacks during unoccupied periods may provide energy savings with no impact on occupant comfort. Proper ventilation control and use of an economizer for free cooling may also contribute significantly to energy savings. 9

10 Building Comfort and Ventilation Analysis This page shows the min/max range of temperature, humidity, and carbon dioxide levels measured during occupied periods. Reducing the range is critical to achieving a building under control that is properly ventilated which allows tenants to be comfortable and productive. The action ratings are based on the worst case found when comparing measured data during occupied hours against established industry guidelines (ENERGY STAR, BOMA, ASHRAE, DOE). Temperature Findings Your building is controlled well with little opportunity for savings. 2 space(s) were too warm at times 0 space(s) were too cool at times 2 space(s) had excessive temperature variation Relative Humidity Findings 10 space(s) had high relative humidity at times 0 space(s) had low relative humidity at times Carbon Dioxide Findings Your building is over-ventilated and can save energy by reducing the overall amount of outside air ventilation 1 space(s) had elevated carbon dioxide levels 6 space(s) had low carbon dioxide levels 10

11 Temperature [Sensor Range: 32 to 100 F; Resolution: 0.1 F; Calibration Accuracy: ± 1 F] The ideal temperature is between 68 ºF and 75 ºF during the heating season and 72 ºF and 78 ºF during the cooling season, with variation of less than 3 ºF. Lowering the heating setpoint and raising the cooling setpoint can save significant energy while maintaining a comfortable and productive working environment. Sources: ASHRAE Standard , BOMA, ENERGY STAR, DOE Alert Lvl Occupied/Unoccupied Heating Setpoint is 72 / 70 Occupied/Unoccupied Cooling Setpoint is 72 / 74 Energy Savings Opportunities Our findings indicate there are several ways to save money by operating your building differently: Energy Recommendations Based on Measurements Calibrate thermostat(s) to reduce temperature variation Verify the controls system is shutting the heating & cooling equipment off Move thermostat(s) to reduce temperature variation Balance air flow within duct system to reduce temperature variation Further Comfort & Energy Recommendations Raise the cooling set point Lower the heating set point Increase the amount of heating set back possible during the unoccupied times Increase the amount of cooling set back possible during the unoccupied times Monitor Statistics Monitor Alert Lvl Min ºF Max ºF Avg ºF %ToR* SV Preschool % 4 Theater % 4 S Art % 2 S Dance % 3 Office % 4 Lobby % 5 Cafe % 4 Ceramic % 4 N Art % 5 Print Rm % 2 These statistics are for occupied times only based on 10 minute averages. * % Time out of Range Spread Value is based on rolling 4hour per ASHRAE Unoccupied Time 11

12 Relative Humidity [Sensor Range: 10 to 95 %; Resolution: 1%; Calibration Accuracy: ± 5%] Optimum comfort and health is achieved when relative humidity is maintained between 30% and 55%. Readings outside these boundaries may indicate ventilation issues which contribute to an increase of energy used to condition the space. Sources: ASHRAE Standard , American Lung Association, Indoor Air Quality Association, BOMA, ENERGY STAR, DOE Analysis and Recommendations Our findings indicate areas in your building that may have issues worth investigating for possible energy savings, and especially if there are comfort complaints. Possible Causes Infiltration of humid outside air Cooling equipment oversized Excessive ventilation during some periods Recommended Actions Reduce air leaks Locate and remove moisture source or install dehumidification equipment Reduce capacity of cooling equipment or install dehumidification equipment Improve ventilation control Monitor Statistics Monitor Alert Lvl Min Max Avg % ToR* Preschool % Theater % S Art % S Dance % Office % Lobby % Cafe % Ceramic % N Art % Print Rm % These statistics are for occupied times only. * % Time out of Range Unoccupied Time 12

13 Carbon Dioxide [Sensor Range: 0 to 2000 ppm; Resolution: 10 ppm; Calibration Accuracy: ± 100 ppm] Monitoring carbon dioxide levels is an important aspect of ensuring a comfortable, healthy and energy efficient indoor environment. At levels above 1000 ppm, air becomes stale and less comfortable to breathe. Levels well below 1000 ppm may indicate excessive outside air, resulting in higher than necessary energy costs due to the need for conditioning of this additional outside air. Sources: ASHRAE Standard , U.S. Green Building Council, Indoor Air Quality Association, Health Canada, BOMA, ENERGY STAR, DOE Energy Savings Opportunities Our findings indicate there are several ways to save money by operating your building differently: Energy Recommendations Based on Measurements Verify dampers are not stuck open or leaky Reduce the amount of outside air ventilation Install demand control ventilation Comfort & Health Recommendations Properly manage the amount of ventilation into the building to maintain appropriate levels. Monitor Statistics Monitor Alert Lvl Min Max Avg % ToR* Preschool % Theater % S Art % S Dance % Office % Print Rm % These statistics are for occupied times only. * % Time out of Range Unoccupied Time 13

14 Lighting Lighting controls and scheduling are some of the easiest low and no cost investments in energy efficiency. Controlling the artificial lights with occupancy or daylight controls and replacing inefficient bulbs can significantly reduce your electrical energy spend. In the graph below, artificial lights are represented by the sharp on/off of the curve, natural daylight by a gradual increase, and direct sunlight by the large spikes. Sources: BOMA, ENERGY STAR, DOE Energy Savings Opportunities Our findings indicate there are several ways to save money by operating your building differently: Energy Recommendations Based on Measurements Verify the light schedule & reduce unoccupied hours operation Further Energy Recommendations Replace inefficient lamps with new high efficiency lamps Install occupancy sensors for individual zones Install daylight controls on the perimeter Reduce after hours use through coordination with the cleaning crews Stated Schedule: 10 average occupied hours Monitor Alert Lvl Measured On-Time Preschool 3.4 hrs Theater 8.01 hrs S Art 4.77 hrs S Dance 3.3 hrs Office hrs Lobby 6.86 hrs Cafe hrs Ceramic hrs N Art 4.74 hrs Unoccupied Time 14

15 Building Description Medical Office Gross Floor Area Number of Workers Weekly Operating 84 % Air- Hours Conditioned % Heated Building Utility Information Electric Utility Information Electric Usage Electric Demand Date kwh Cost KW Cost 2/1/11 43,760 $3,517 0 $0 3/2/11 42,880 $3,507 0 $0 3/31/11 53,120 $4,109 0 $0 4/29/11 64,640 $5,152 0 $0 5/31/11 75,920 $6,091 0 $0 6/29/11 48,040 $4,882 0 $0 7/28/11 99,160 $8,892 0 $0 8/29/11 94,360 $8,364 0 $0 9/27/11 71,440 $6,569 0 $0 10/27/11 68,880 $5,493 0 $0 11/27/11 61,720 $4,979 0 $0 1/3/12 92,640 $7,729 0 $0 Fuel Utility Information Fuel Usage Date Usage Cost 3/1/11 4,575 $3,088 3/31/11 3,266 $2,093 4/29/11 2,171 $1,695 5/31/11 1,704 $1,338 6/29/ $386 8/3/ $359 9/2/ $249 10/3/11 1,922 $1,429 11/2/11 2,270 $1,650 12/2/11 3,750 $2,474 1/3/12 4,622 $2,963 2/1/12 3,913 $2,421 TOTAL: 29,327 $20,145 TOTAL: 816,560 $69,284 0 $0 15