GreenStep City Best Practices: Buildings and Lighting
Efficient Existing Public Buildings No. 1
Benchmark energy and water usage, identify savings opportunities in consultation with state programs, utilities and others to implement cost-effective energy and sustainability improvements.
Invest in larger energy efficiency projects through performance contracting or other funding or through smaller retro-commissioning/retrofit projects in city-owned/school buildings.
Retrocommissioningcorrects and enhances how building equipment and systems function together, resolving problems that occurred during design or construction or that have developed during the building's life. If the building went through the quality-assurance process called commissioning when initially designed and constructed, then a recheck is called recommissioning and is recommended to do once every 5 years, for a typical energy savings of 10%. Retrofittingimproves building components, upgrades operating systems and equipment, and installs energy-efficient appliances.
Audits and Studies:
Before making changes to a building, an energy audit is done at one or more (ASHRAE) levels, which range from easy/cheap to harder/costlier:
Level 0 - Benchmarking (using historic energy data)
The MN Department of Commerce’s Local Energy Efficiency Program (LEEP) helps local units of government complete Investment Grade Audits for smaller energy projects ($50-$350,000). LEEP is a useful tool to identify a range of energy conservation measures with varying payback terms. LGUs requiring financial assistance encumbering funds for an IGA are eligible for Commerce’s Energy Audit Loan Program, which can be repaid or rolled into an energy project’s financing.
Note that to optimize costs/benefits, the quick payback of lighting retrofits (BPA 1.2) is often best paired with additional/longer payback equipment changes to increase the ultimate savings to a city and to typically bring city buildings down to a B3 Index Ratio of 0.7 (with 1.0 being operations as expected if performing to the currently MN Building Code).
The Guaranteed Energy Savings Program (GESP) from the MN Dept. of Commerce is available for state and local governments, school districts, and institutions of higher learning to lock in verifiable ongoing energy savings (using B3 data) through vetted contractors and a master performance contracts to achieve deeper retrofits without capital appropriations.
DSIRE (Database of State Incentives for Renewables and Efficiency) is a one-stop source of information on the status of state programs and local utility programs, policies, rebates and other incentives. Note that Minnesota companies can take over rebate administration for city and private projects to increase the return on energy investments.
The City of St. Paul, for example, has an Energy Conservation Investment Fund, a revolving loan account that supports energy-efficiency investments - retrofits of existing facilities - with a documented payback of less than 10 years for city-owned buildings. Green Revolving Funds: An Introductory Guide to Implementation and Management (Sustainable Endowments Institute: 2013) explains and provides background on internal, self-managed revolving loan funds that finance energy efficiency improvements.
See model procurement and contracting documents from the Energy Services Coalition, a public private partnership promoting the benefits of, providing education on, and serving as an advocate for the widespread use of energy performance contracting.
Complete retrocommissioning and/or retrofitting work on one building. Summarize the actions taken. Update the B3 Building Editor as needed and change the Baseline Time Period to report energy/cost savings.
Complete retrocommissioning and/or retrofitting work financed by an energy performance contract, utility rebate or other means on two or more buildings. Post a print screen of B3 data to report energy/cost reductions.
Complete 1 and 2 Star criteria. In addition, use GESP or implement an internal program or use an external program/vendor that institutionalizes, and provides funding / incentives for, ongoing reductions in energy use by city-owned buildings (e.g. internal loan fund, shared savings with employees, capital budgeting based on energy savings, performance incentives and accountability, etc.).
Who's doing it
Bemidji - 3 star
Date action report first entered:
Date of last report update:
Year action initially completed:
Implementation details:
The city of Bemidji was one of the first in the state to utilize the Guaranteed Energy Savings Program, or GESP. GESP is essentially performance contracting, with a few added benefits. Bemidji used GESP to undertake a $2.5 million dollar efficiency project. Nine city buildings underwent an energy audit through the Retired Engineer Technical Assistance Program, and then made the efficiency upgrades according to the RETAP audit. Also, much of the cities outdoor lighting was upgraded to LEDs.
Outcome measures/metrics/money saved:
Bemidji realized a one-time rebate of $122,000 and is anticipating on saving $120,000 each year in utility and maintenance costs.
Fire Station 1:
All of the following changes were started in 2010 and completed by October of 2011. Some of the changes were the result of recommendations from an audit performed by Dakota Electric. Some changes, like the replaced furnace, were scheduled replacements. Most HVAC systems that will be replaced in Burnsville in the future will all be replaced with energy efficient models if funding allows.
-Exhaust ventilation controls were installed
-Programmable thermostats were installed
-Outdoor ventilation controls were installed
-All existing vents are now tied into the furnaces
-The furnace was replaced with a high efficiency condensing furnace
-Bay heaters were replaced with infrared heating
-Outdoor lighting fixtures began converting to LED fixtures.
Dakota Electric provided a $3,000 rebate for the air source heat pumps. CenterPoint Energy provided funding for the high efficiency furnaces.
Burnsville City Hall:
-In 2007 the chiller was replaced with a variable drive.
-In 2010, a TPL Roof with R34 insulation was installed
-Installed an Energy Management System
-Converted all the pneumatic VAV boxes to electronic or digital control
-Hot and cold water valves have been replaced with digital and electronic controls instead of air
-A dozen outdoor fixturs have been replaced with LED lights.
-In 2011, Maintenance Staff began converting interior lobby lights, property lights and several other areas to LED (26 LED fixtures in total).
-In the process of signing a contract to install a high efficiency condensing boiler in the building. This will be completed in 2012.
The following items will be completed in the next couple of years:
-Circulating pumps will be replaced with variable frequency drives
-Humidifiers will be replaced with more energy efficient models
-All HVAC equipment will will be tied into the energy management system.
In 2012, Burnsville created an Energy Efficiency Fund. The fund is overseen by Maintenance Supervisor Gary Novotny. This fund incentives purchasing energy efficient products by matching rebates and by selectively paying for energy efficient products that have longer paybacks, such as LED lighting. Currently the fund is being used to pay for outdoor LED lighting fixtures. The results of the program will be reported in Burnsville's Annual Report for it's Sustainability Plan. In addition, going forward, Gary Novotny and Sue Bast will report progress on the GreenStep Cities Site.
Outcome measures/metrics/money saved:
Fire Station 1 energy consumption reduced 13.76% post retrofitting.
City Hall energy consumption reduced 15.65% post retrofitting.
Burnsville created its Energy Efficiency Fund in 2012. The results of the program will be reported in Burnsville's Annual Report for it's Sustainability Plan. In addition, going forward, Gary Novotny and Sue Bast will report progress on the GreenStep Cities Site.
Energy Use was reduced by 1,058,447 kWh and 15,668 Therms during years 2011 to 2013 by implementing energy measures, primarily lighting and high efficiency boilers, in over 50 city-owned buildings and other energy saving measures.
Outcome measures/metrics/money saved:
Annual Electric energy use and total cost savings from energy efficiency measures:
2011 - 288,334 kWh saved and $37,238 costs saved
2012 - 438,131 kWh saved and $51,201 costs saved
2013 - 271.862 kWh saved and $23,533 costs saved
The 20-40-15 initiative, first rolled out by the City of Eden Prairie in December 2006, calls for the City to improve energy efficiency in all of its facilities by 20 percent, increase the fuel efficiency of its vehicle fleet by 40 percent, and accomplish these goals by the year 2015.
The City is working closely with McKinstry Company, a firm touted by President Barack Obama as a “model for the nation” for its work in retrofitting schools and office buildings throughout the country to make them more energy efficient.
The City’s partnership with McKinstry Company guarantees the estimated savings from the projects it recommends will pay for the cost of implementing those projects as well as the firm’s consulting fees. If the savings fall short of the costs the City incurs, McKinstry Company will make up the difference.
The City encourages Eden Prairie residents and business owners to become more energy efficient and embrace environmental stewardship. The January 2009 issue of Life in the Prairie includes some great tips to get started, as well as other resources to help in this effort.
Outcome measures/metrics/money saved:
The City is implementing the projects in phases. Some of the actions the City has taken include replacing standard stop lights with light-emitting diode (LED) lights that use 90-percent less energy. The City has also added motion sensors to control lighting in meeting rooms, adjusted the timers which control lighting and HVAC after hours, and re-lamped several light fixtures and signs to utilize energy-efficient LED bulbs. Repairs to City buildings have helped reduce the amount of heated and cooled air that escapes to the outside.
The City encourages Eden Prairie residents and business owners to become more energy efficient and embrace environmental stewardship. The January 2009 issue of Life in the Prairie includes some great tips to get started, as well as other resources to help in this effort.
In 2011 the City contracted with McKinstry under the Guaranteed Energy Savings Program. Under the contract, the 12 largest municipal facilities were audited. This energy audit identified the following efficiency improvements and implemented: $141,000 building envelope improvements, $18,000 water conservation improvements, and $310,000 interior lighting retrofits. This retrofit project included 11 separate city buildings. In 2013 the City will consider a second round of energy efficiency retrofits.
Outcome measures/metrics/money saved:
The performance contract project was projected to reduce over 540,000 kWh and 19,600 therms of gas on an annual basis, reducing the Citys carbon footprint by 540 metric tons of CO2 annually and qualify for a guaranteed annual savings of approximately $54,000. B3 data confirmation of these savings is elusive.
Conducted full scale assessment of all City owned building. The assessment included a wide variety of BP's for efficiency, controls, renewables, etc.
Outcome measures/metrics/money saved:
Began implementing efficiency improvements through performance contract and internal project delivery by City staff. These savings have resulted in almost $1,000,000 in savings since 2009.
The City has completed a study with Apex Efficiency Solutions that reviewed each of the City's facilities for energy savings, operations and maintenance savings, and potential incentives available from the utilities. With lighting upgrades, HVAC improvements, and building envelope improvements, potential savings total over $161,000.
The LLAP continues our sustainability efforts by working to install 200Kw solar PV on the
Reservation and implementing a large 22 building Guaranteed Energy Savings Project that could save LLBO over $800,000 in energy savings and 9,839 metric tons of GHG emissions per year.
The city invested in energy-efficient and environmentally friendly technology, equipment, and building materials in the construction of its new police station/city hall, which opened in 2019. The $254,222 in upgrades were funded by the city ($204,371) and by an incentive from Xcel Energy and CenterPoint Energy ($49,851). According to the Energy Design Assistance Verification Report prepared by the Willdan Group, Inc., the city will save approximately $50,932 in energy costs annually, meaning that it will take about four years to realize gains on the initial investment (with incentive). The new building includes a high efficiency gas boiler (95% efficiency rating), which utilizes condensing technology to recover heat, reducing energy usage and costs. The air conditioning system uses direct expansion technology and compressors, cooling the air supplied to the building in which it is located by using a refrigerant vapor compression and expansion cycle. The building heating water pump includes a variable frequency drive, which allows for variation in pump speed, consuming less energy. The control system for the building’s heating, ventilation, and air conditioning systems utilize variable air volume to allow for varying airflow at a constant temperature. The system allows for better control as compared to standard systems, which feature constant air systems that cannot be adjusted. The new building includes carbon dioxide sensors with demand control ventilation to reduce the need for outside air during times of partial occupancy. Garages throughout the building are equipped with carbon monoxide sensors that control ventilation rates so that ventilation is reduced during times of low occupancy. There are also direct fired gas furnaces used exclusively for the heating of the garages. Materials that reduce thermal bridging (movement of heat) were used for building walls and roofing and windows are resistant to sunlight. Automatic dimming daylighting controls are used for lighting throughout the building in offices, meeting rooms, parking garages, and public areas. Motion sensors have been installed in most areas and when sunlight is more prevalent, lighting levels automatically decrease. A high efficiency water heater (95% efficiency rating) was installed and the building is equipped with several water bottle filling stations.
The city's Energy Improvement Project (#894) with McKinstry included major improvements to the New Hope Ice Arena, such as an efficient refrigeration system, new dehumidification system, and new roof on the north rink. Improvements to city buildings (City Hall, Public Works, Ice Arena, Golf Course, Pool) included interior and exterior lighting and building envelope improvements. The project was completed in December of 2012. Other improvements independent from the McKinstry project include replacing garage doors with energy efficient well-insulated doors at the city's Public Works facility. There are also plans to replace HVAC systems in all city buildings by 2017.
Outcome measures/metrics/money saved:
The $254,222 in upgrades for the new city hall/police station were funded by the city ($204,371) and by an incentive from Xcel Energy and CenterPoint Energy ($49,851). According to the Energy Design Assistance Verification Report prepared by the Willdan Group, Inc., the city will save approximately $50,932 in energy costs annually, meaning that it will take about four years to realize gains on the initial investment (with incentive).
Performance savings realized for the first year was $96,381, $25,000 greater than what was guaranteed by McKinstry.
The City recently has utilized performance contracting for several projects. The Energy Efficiency and Biofuel Project outlined energy efficiency and the installation of a biofuel recovery system at the NEW Recovery Facility. The Energy Efficiency work included HVAC, building envelope, lighting, and process upgrades. The Street Light Improvement Project (SLIP) focused on all the city-owned streetlights and replacing them with energy efficient systems.
Outcome measures/metrics/money saved:
The Energy Efficiency and Biofuel Recovery Project at the NEW Recovery Facility is fully complete. This project saves 1.6 million kWh annually. The Biofuel Recovery also generates renewable energy. The Street Light Improvement Project (SLIP) was completed in 2018. The SLIP Project saves 2.4 million kWh each year.
Remodeled city library with improving insulation and putting on addition. Goal to improve heating and cooling costs. Keep utilty cost the same with 40 X 40 addition in place.
Conducted a thermal imaging survey to determine energy loss in every public building to prioritize retrofit/retro-commission projects; installed building operation technology from 75F, this includes a CCU, Smartstats, occupancy sensors, etc.
Outcome measures/metrics/money saved:
Reduced then fixed the city’s library utility costs a year after installation; fixes city hall's operations and keep them on a schedule.
Alliant Energy conducted energy audits at major city-owned facilities in 2012. The attached document outlines the changes that have been made at each facility.
Austin Public Schools completed boiler/water heater upgrades at Banfield Elementary School and Ellis Middle School using an energy performance contract. The City of Austin completed retrofits of T8 fixtures with LED lamps. Austin Utilities offers several project financing/incentive programs that initiated the projects. The LED retrofits received 80% of the project costs in rebates with less than a 2 year payback.
Outcome measures/metrics/money saved:
Banfield achieved a 17+% reduction in energy use and Ellis saw a 1% decrease in energy use as shown in the attachment.
Cottage Grove received a renovations grant from the Office of Energy Security to retrofit three city buildings. City hall/public safety building, public works facility and fire station 2. The retrofits included replacing inefficient lighting to be replaced with high efficiency fixtures as well as occupancy controls.
The city received a $657,000 Federal Energy Efficiency and Conservations Block Grant to upgrade city owned buildings to make them more energy efficient. The consulting firm of McKinstry oversaw the project and leveraged the grant dollars with utility rebates that resulted in $1.2 million in improvements.
The City receives rebates from Dakota Electric and other utilities as a result of the projects funded through the Energy Efficiency and Conservation Block Grant. Examples where rebates were received include building recommissioning work and interior lighting upgrades. The City also participates in Dakota Electric's load shedding program to reduce peak demand electricity needs, which results in a rebate to the City.
Outcome measures/metrics/money saved:
The city received a $657,000 Federal Energy Efficiency and Conservations Block Grant.
The direct impact of the retrofits resulted in significant energy, dollar and CO2 savings for the buildings receiving the retrofits; in particular the Municipal Building, Police Building and Maintenance Facility.
Underperforming buildings will have a targeted plan to make modifications to meet defined goals. In particular, each building that is currently underperforming after the initial retrofits will have a 3-5 year plan wherein energy enhancements that were not included as part of the initial energy audit will be planned and budgeted for.
The continual tracking of energy use and costs through B3 will provide the tangible data to prioritize which buildings need the most attention to meet the energy saving goals.
- The City frequently receives rebates from Centerpoint Energy for heating upgrades.
- The City applied for and received an $87,000 grant from the Federal Stimulus package (ARRA) to upgrade lighting and heating systems in the Elk River Ice Arena.
- Received over $10,500 in state and utility rebates for the ice arena alone.
The City has retrofitted or designed the during construction phase several public buildings including the Public Works and Water Treatment building for the purpose of energy efficiency. Sky lighting and air circulators exist in the new public works building and . No energy performance contract was used to finance the work done on these properties. The City completed a joint project with Xcel Energy in November, 2018 to convert all 81 streetlights to more efficient LEDs
Outcome measures/metrics/money saved:
The is estimated to see a monthly energy kwh savings of 2,353 and cost savings of $500.year.
Fond du Lac Band of Lake Superior Chippewa - 2 star
Date action report first entered:
Date of last report update:
Year action initially completed:
Implementation details:
In 2016, FDL contracted Noresco to do an energy audit as part of a strategy to meet our 2007 goal to reduce fossil fuel emissions 20% by 2020. The audit identified energy savings opportunities and conducted lighting retrofits, boiler replacements, chiller plant and air handling unit upgrades, water conservation measures, and building level control optimization.
Outcome measures/metrics/money saved:
There is a six year projected payback on all installed equipment from the energy audit. The installations will save FDL $64,000 per month from the date of completion of the project. As of 2018, FDL has reduced emissions by over 40%.
After the Retap audit we received a grant from the Department of Energy for new doors and lighting for the Hoffman Square building. It was completed by September 2010. We completed new lighting in the Hoffman gym. We also completely gutted 2 buildings and renovated them with energy saving insulation, lighting, etc. We now have healthcare providers there so residents do not have to drive out of town.
Hopkins had two buildings fall into the bottom third of the B3 energy performance ranking: City Hall and the parking ramp. In November '10 City Hall received new boilers and the parking ramp is scheduled for new lighting by Spring '11. Both projects are eligible for rebates; the boiler room has been submitted for 3892.00. The reduced use of natural gas in 2009 was due to the decision to take the boilers off line during the summer months instead of running them year round. The fuel usage so far this year for the new boilers is running about 30-40% below last year's usage. The boiler savings are starting to show up only 3 months after replacing the old boiler. The City's estimated savings is around $8,000.
Outcome measures/metrics/money saved:
City of Hopkins fuel costs before and after boiler upgrade (2009 cost/2010 cost) Sept-Oct: $937/$96. Oct-Nov: $1165/$759. Nov-Dec: $2667/$1786.
#1 - The La Crescent Fire Station and Community Building went through a extensive renovation to install energy, safety, and accessibility upgrades. These upgrades were done from 2015 to completion in March 2016 and included conversion to all LED lighting, weather stripping, sealant, HVAC replacements, and integrated communications and controls for heating and cooling. As of Fall 2016, La Crescent was chosen to be a part of the Made In Minnesota program.
#2 - The community ice arena has converted all indoor and outdoor lighting to LED lighting as of 10.31.16.
City Hall energy improvements: We contracted with a certified building engineer to conduct an evaluation of our city hall and made the recommended improvements to increase energy efficiency. We installed new roof vents, added insulation to the ceiling, replaced entry doors,added outside wall insulation and new siding. Additionally we made improvments to our furnace system and improved water runoff with new gutters which drain to a grassy area rather than draain to an impervious surface.
Outcome measures/metrics/money saved:
We are comparing our energy expenses currently to energy expenses previous to the improvements.
Energy audits were completed on all City buildings and savings opportunites identified. Buildings with the most potential for energy savings with the lowest cost were targeted for efficency improvements.
Outcome measures/metrics/money saved:
Lighting retrofits were completed at City Hall, Wastewater Facility, Parks Department, Airport, Ambulance building, and Merit Center, replacing all T-12 lighting with high performance T-8 lighting.
City Hall & Community Center retrofitted with energy efficient lights (2015), Random Park Building (2016), all trail lights to LED (2017/2018) and Hilview and Lambert Park Building and Hockey Rink Lights will be retrofitted in 2020.
In the late 1980s, the City of Red Wing worked with NSP to do a lighting retrofit at City Hall, Public Works, and the Library that they paid back with the energy savings created because of the retrofit.
Completed. Multiple projects have been undertaken including higher efficiency HVAC systems, LED lighting retrofits, automatic doors and window replacement.
The city has retrofitted 2 buildings and is in the process of recommissioning a third. New insulation and drywall was installed at the Police Garage. New insulation and vapor-sealing was installed on the rim joist of the Police Station. The Rogers Activity Center is being recomissioned and a new building controls system is being installed.
Outcome measures/metrics/money saved:
We will post a print screen of the results in B3 when they become available in the next billing period.
After doing an energy audit of all city buildings the city chose to make energy upgrades (relamp/retrofit) in all buildings. We could have saved money by not doing the cold storage building (least energy savings)but we chose to do all buildings and take the total energy savings.
Outcome measures/metrics/money saved:
Work was completed before 12/31/10 so we will have a full year of data to check on our energy savings.
• In 2009, the City of Saint Paul received a grant from the U.S. Department of Energy as part of the American Recovery and Reinvestment Act. The grant along with utility rebates have allowed the city to completed over 100 energy efficiency projects in 60 municipal facilities, reducing its energy use by 30 percent. Case studies were developed for city-owned buildings and parking ramps that underwent energy efficiency retrofits. The majority of the projects have a projected payback period of less than five years.
In 2010, the Police Department replaced its water heater and boiler with a high efficiency water heater and boiler.
In 2012, the City of Shakopee along with the Metropolitan Council and CenterPoint Energy performed a series of retrofits for the Blue Lake Wastewater Treatment Plant. The heat recovery system installed on the dryer scrubber system which allows the system to recover 1.85 MMBtu/hr of waste hot water from an odor control system to maintain the digester’s operating temperature of 98 F, eliminating all heating requirements of the digesters whenever the dryer is operating. The biogas will be used to fuel boilers for heating the control building. Solids removed from the wastewater are dewatered, dried and pelletized for use as an agriculture fertilizer, under a public-private partnership between MCES and the New England Fertilizer Company (NEFCO) and an additional treatment process, anaerobic digestion, produces methane gas that helps power the solids drying equipment. The existing dryer burner equipment was retrofitted to burn either natural gas or the in-house produced biogas with 55-60% of the heat content of natural gas. Other improvements made at Blue Lake include premium efficiency pump motors, motor drives, and the replacement of air diffusers and additional valves have provided better control over dissolved oxygen and improved oxygen transfer.
During the October 2016 remodel, the Community Center upgraded 50% of the interior lights to LED lighting and installed Variable-Frequency Drives.
In 2017, the Public Works building replaced 12 out of its 22 parking lot lighting fixtures and converted to LED lighting- 350 W bulbs replaced 50 W LED bulbs.
In 2017, the Fire Station parking lot lighting fixtures converted to LED lighting - 400 W bulbs replaced with 100 W LED bulbs.
In 2018, the exterior lights on the Community Center were upgraded to LED lighting. In 2019, the upper parking lot lighting was upgraded to LED lighting and computer monitors were upgraded from older CRT monitors to newer LED monitors to improve energy efficiency.
Outcome measures/metrics/money saved:
The use of the anaerobic digestor produced energy savings equivalent to the annual gas usage of 900 residential customers per year and reduced consumption of purchased natural gas by 80%. The heat recovery system installed on the dryer scrubber system which allows the system to recover 1.85 MMBtu/hr of waste hot water from an odor control system to maintain the digester’s operating temperature of 98 F, eliminating all heating requirements of the digesters whenever the dryer is operating.
The Metropolitan Council projected and documented energy savings of 80,000 Dth/year is about 80% of the dryer’s pre-project energy consumption and reduces the mass of the solids loading to be dried by 30%.
In 2014, the City made an effort to reduce its energy usage at City Hall by replacing many of the lights with more energy efficient LEDs. In addition to switching out light bulb, the City became stricter and more refined in temperature control and air handling unit regulating. This has led to substantially monetary and energy savings.
Outcome measures/metrics/money saved:
Since the switch, City Hall is using 40,000 to 50,000 fewer kWh a month. This has saved the City between $500 and $5000 monthly on energy costs.
Performance contracting with McKinstry for largest city buildings. Began in 2008 and concluded in 2014.
Outcome measures/metrics/money saved:
Annual savings of 909 metric tons of CO2 over the course of the project. Approximate annual reduction of 936,402 kWh of electrical use and 49,584 Therms
All city buildings have had recommissioning studies completed, as well as lighting retrofits.
In 2007, Woodbury City Hall was remodeled, including a 13,841 sq. ft. addition to the building. Energy improvements included a geothermal system, a south facing glass facade to maximize daylight, energy efficient mechanical and electrical systems, energy efficient lighting, and occupancy sensors. An energy management system allows the city to control the energy use based on occupancy. The project also featured installation of a green roof, porous paver parking stalls, low-flow water fixtures, a rain garden, and the installation of "Grasspave" and "Advanced Turf" along walking paths to handle truck loads without adding impervious surface.
In 2009, Woodbury replaced the existing ice arena refrigeration system at Bielenberg Sports Center with an energy-efficient geoexchange (or ground source heat) system. The new system is estimated to prevent 1,024 metric tons of CO2 emissions and result in $100,000 in utility cost savings. The project also included installation of low emissivity ceilings, a new energy management system, and fixture retrofits for water conservation.
During the Summer of 2011, the city remodeled and expanded the public safety building to include a geothermal system for heating and cooling. In October 2012, a 40kW solar PV array was installed on the building. The project also included the addition of a parking garage for public safety vehicles. Since the vehicles previously idled for long periods to keep computer and medical equipment from freezing, the garage eliminated the need for continuous idling. Fuel savings averaged througout the year equals 1,100 gallons of fuel each month.
Apple Valley received federal Energy Efficiency Conservation Block Grant funding, which allowed the city to undertake efficiency upgrades in eight buildings. Utility rebates provided additional funding for many projects.
Demand based controls that measure CO2 levels have been installed to manage the large air handling units in the Civic Plaza. Where applicable occupancy sensors have been installed to control lighting in offices, park buildings and vehicle storage garages.
The City Facilities Maintenance Supervisor has been switching sections of the existing buildings over to LED as lighting fails or is due for upgrades, instead of waiting for a complete building project. See for example the LED outside lighting done for the liquor store attached.
Where appropriate, lights are on timers (hallways, restrooms, etc.) As HVAC equipment wears out and is replaced, it is replaced with Energy Star/energy efficient models.
After conducting an energy audit at city hall, lighting in the entire building (city hall, council chambers, public works garage, and fire department) was retrofitted to a more efficient standard. In 2012, the City worked with Lightinghouse USA to install LED bulbs in approximately 40 decorative street lights.
Outcome measures/metrics/money saved:
With the assistance of Xcel Energy rebates, the expected payback for the upfront capital costs is expected to be less than two years.
In 2023, the City replaced the boilers at City Hall with two new energy efficient Lochinvar Crest Condensing boilers with up to 96.2% thermal efficiency, lower emissions, and has remote connectivity and smart touch controls. The City received a $9,600 rebate through Minnesota Energy Resources for installing higher energy efficient equipment.
In 2023, the City also replaced the water heater at the Ice Arena with a HTP Phoenix water heater with 96% thermal efficiency. The City received a $500 rebate from Minnesota Energy Resources as well.
The City has partnered with Xcel Energy and the Center for the Energy and Environment on a number of retrofits including:
Replacing the fire station cooling unit with a more energy efficient model.
Replacing the fire station cooling unit with a
Replacing the lighting at the City Hall and liquor store with LED lighting
Replacing the variable frequency drive motor at the Marion Hills Water Treatment Plant.
The City has also independently replaced all of the lighting at Fire Stations 2 and 3 with LED lighting.
3 New 97% high efficency mini boilers were installed in the Grand Rapids Fire Hall in 2011 replacing the 78% ribbion type boiler that were 25 years old.
The City completed a full lighting retrofit of the Isanti Community Center in June of 2014. All light fixtures were converted from T12 fluorescent fixtures to LED.
To be implemented Spring 2016, the Isanti Indoor Arena will be converting their manual air exchange system to an automatic system programmed on a timer which will also be tied into an air monitoring system for higher efficiency of only needing to run when necessary.
Outcome measures/metrics/money saved:
A table is attached showing the savings from 2014 to 2015.
1. The exterior of City Hall was retrofitted with LED and Dark-Sky compliant lighting.
2. We are in the process of entering the GESP program for our ICe Arena.
Outcome measures/metrics/money saved:
We will be tracking energy usage at City Hall to guage the effectiveness of our new lighting.
In 2017 the city completely remodeled city hall and the public library integrating updated technology and energy efficient lighting. The building was made 100% ADA compliant. The LED lighting with equipped with dimmers and occupancy sensors.
Outcome measures/metrics/money saved:
As this was a complete remodel with an addition, we really have nothing to compare the energy savings to, but using energy efficient products with dimmers and occupancy sensors ensures that lighting is being used efficiently and will shut off automatically within a few minutes if someone forgets to shut off the light when they leave. Blue prints, energy bills, dimmer and sensor specs are available if you need anything else to verify this step.
Several retrofit projects have been completed in City facilities over the years. One example is the Energy Efficiency and Conservation Block Grant program in 2009 which allowed the City to make the following improvements:
Replacement of two boilers at City Hall with more energy-efficient boilers.
HVAC efficiency upgrades at City Hall.
Energy efficient lighting upgrades at the Maplewood Community Center and Goodrich Park.
Yearly since that time the City has continuously updated its City facilities with energy efficiency improvements through various funding mechanisms, including energy grants and capital improvement investments. The energy savings are tracked in the City's B3 program, which reflects the energy and cost savings of each project.
Fire Station 2019 remodel included LED retrofit and HVAC upgrades for improved ventilation.
In 2017 and 2018 Mendota Heights worked with a solar energy consultant group to provide up to 140-KW of solar energy production at various city-owned sites, including a 40-KW solar field at City Hall, a 60-KW rooftop system at the Public Works facility and two smaller 20-KW rooftop systems at the Par 3 Golf Course and Fire Station facility.
The City Initiated Roof Top Unit (RTU) replacement project at the New Brighton Community Center (NBCC) using Trane as a vendor through the US Communities Government Purchasing Alliance. This project is scheduled for completion in September of 2016.
The efficiencies that can be gained by following the Trane recommendations will allow the City to maximize the comfort of the environment for the building’s users while reducing payback time and maximizing control of the building.
Trane completed a study on the performance of the current HVAC system at NBCC by utilizing data logging devices that were installed at various locations inside the building. The data found shows the current RTU’s are not working at optimal levels. This impacts the comfort level of NBCC visitors and doesn’t allow the NBCC to operate at peak efficiency. It is also demanding on the RTU’s as they are forced to work harder to overcompensate for the various swings in temperatures. This results in higher energy bills and potential repair costs. The RTU’s are also not working at optimal levels due to the units being near the end of their useful life.
An absolute necessity to utilizing any new HVAC system to the fullest extent possible is to replace the current pneumatic controls as part of this project. The NBCC’s current outdated pneumatic controls will be replaced with Direct Digital Controls (DDC). DDC will allow greater control in various areas of NBCC.
The City will seal leaks that have been identified in the exterior wall and roof deck connections as well as window and door frame leaks
during the NBCC project to resist infiltration of air, water, heat, light, and noise transfer from exterior to interior, or from interior to exterior
LEDs will replace the current fluorescent and Compact Fluorescent Lamps (CFL) used at NBCC. This will reduce the amount of energy necessary to operate NBCC and provide high quality lighting. Based on the longevity of LED bulbs will require less staff time to replace when they have burned out. Another maintenance issue that will be resolved is it will no longer be necessary to replace the ballasts to light fixtures, reducing both the equipment cost and again staff time to perform this task. Currently there are different types of lighting fixture types used at NBCC. This includes LED fixtures that were installed as part of the locker room/restroom renovation project, fluorescent tubes and CFL’s as well as metal halide fixtures that provide exterior lighting at NBCC. There are approximately 2,000 fixtures and lamps that would be retrofitted to LED. New LED's are planned for installation in August-September.
Outcome measures/metrics/money saved:
The new RTU's will provide 15-20 years of energy savings.
Energy use data following the project completion dates will be used to compare to existing B3 database records.
This retrofitting project replaced 20+-year old HVAC equipment at Oakdale City Hall with new high-efficiency equipment. As part of this project, the following improvements were made:
a. Boiler replacement: The aging boiler system was removed and replaced with 2 Hydrotherm KN-series cast iron high-efficiency boilers rated at 600 MBH input - rated 99% efficient with an expected yearly energy cost savings of $1,900;
b. Condensing unit replacement: The 20-year old condensing unit was replaced with a Carrier 40T unit with an eer rating of 11.5, R410a and VFD installation. The expected yearly energy cost savings is $5,600 over the current equipment;
c. Rooftop unit replacement: The 25 year old low-efficiency rooftop unit was replaced with a Carrier 20 ton capacity unit with an 11.5 eer rating.
The project received $13,900 in rebates from Xcel Energy for installing energy efficient technology.
The City used a US Communities joint purchasing contract with Graybar Electric to retrofit the interior and exterior fixtures at the Community Building to LEDs' The exterior fixtures were also upgraded to protect the dark sky. The cost of the upgrades was $33,285 which was reduced by Xcel rebates of $5,069.
Outcome measures/metrics/money saved:
The cost savings are estimated to be $3,240 per year which provides a 8.7 year payback based on energy savings. The actual payback is expected to be much quicker since most of the fixtures are in the Community Room that has high ceilings where bulb and ballast replacement costs are significant.
