V. 1. Application 2017-08-TA Alternative Energy Systerms Zoning Text Amendment
April 24, 2018 Planning Application 2017-08-TA
Alternative Energy Systems Text Amendment
Proposed Action: Move to adopt Planning Commission Resolution 2018-02, recommending
the City Council approve an ordinance amending the City Code related to solar energy systems.
Overview In late 2017, staff presented information from the SolSmart program, a national
designation program designed to recognize communities that have taken key steps to address
local barriers to the implementation of solar energy systems. During that review, staff identified
the need for a zoning text amendment to promote the use of solar energy systems, remove
regulatory barriers and create a clear regulatory path for approval. City staff studied this issue
and reviewed various items with the Commission during the first quarter of 2018. Based on
information from the SolSmart program, the City’s sustainability goals, existing energy
conditions in Hopkins and research on solar energy systems standards in other communities,
staff has prepared the attached draft Solar Energy Systems Ordinance for consideration. The
ordinance is based on the Minnesota Model Solar Ordinance but has been modified to address
specific needs and conditions in Hopkins. Should the City approve the proposed ordinance, it
would make the following changes:
• Establish the purpose and intent behind the proposed regulations.
• Define specific terms associated with solar energy systems.
• Detail allowable uses by zoning district.
• Create specific performance standards for solar energy systems
• Outline a review process and necessary application materials.
• Allow for deviations based on criteria unique to solar energy systems.
• Place reasonable limits on private groups to restrict solar energy systems.
• Encourage protection of solar access through easements.
Primary Issues to Consider
• Prior Action by the Planning & Zoning Commission
• Existing Energy Conditions in Hopkins
• Legal Authority
• Proposed Zoning Changes
Supporting Information
• Planning & Zoning Commission Resolution 2018-02
• Draft Solar Energy Systems Ordinance
• Great Plains Institute Report - Existing Energy Conditions in Hopkins
Financial Impact: $ N/A Budgeted: Y/N ____ Source: _____________
Related Documents (CIP, ERP, etc.): _________________________________________
Notes:
Planning Report 17-08-TA
Page 2
Prior Action by the Planning & Zoning Commission. In July and August of 2017, staff
presented information from the SolSmart program, a national designation program designed to
recognize communities that have taken key steps to address local barriers to the implementation
of solar energy systems. During that review, staff identified several steps for Hopkins to achieve
SolSmart designation. Chief among them was approval of a zoning text amendment to promote
the use of solar energy systems, remove regulatory barriers and create a clear regulatory path for
approval. In January, the Commission reviewed existing energy conditions in Hopkins, the State
of Minnesota’s Model Solar Ordinance and directed staff to do further research and schedule a
presentation from SolSmart staff. During the February meeting, the Commission heard a
presentation from SolSmart staff on existing energy conditions in Hopkins, different types of
solar energy systems and various zoning options. Last month, the Commission opened the
public hearing on this item but heard no comments and continued it to the April 24th meeting.
Existing Energy Conditions in Hopkins. The Existing Energy Conditions report provides a
detailed profile of energy use in Hopkins and the renewable energy resources available in the
community. Overall, this information suggests that increased use of renewable energy would
help reduce greenhouse gas emissions (GHG) in Hopkins. More specifically, the report suggests
the use of solar energy by commercial buildings, would have the largest impact on GHG
emissions. The report finds the vast majority of energy used and emissions produced in
Hopkins come from buildings, with 75 percent of all greenhouse gas emissions coming from
residential and commercial buildings. Transportation makes up the remaining 25 percent of
energy use and GHS emissions. Of the GHG emissions from building, the commercial sector
makes up 72 percent of GHG emission from buildings. In addition, most of the GHG
emissions from buildings come from the use of electricity (57%) compared to natural gas (43%).
It is also important to note that while commercial buildings consume a majority of the energy,
they comprise only 20 percent of the square footage and represent little over 10 percent of the
number of buildings in the community. From this information, the report concluded focusing
on commercial and industrial building energy was a potentially high-impact strategy for the City.
The report goes on to calculate Hopkins’ “solar reserve” or how much solar energy is
reasonability economically available for development (similar to how oil or gas reserves are
measured). The total capacity of only the commercial rooftop solar resource in Hopkins is 86
MW, equal to approximately 55 percent of all electricity consumed in the City. The report also
notes that if buildings undergo high levels of energy efficiency investment, the solar resource
could meet an even higher percentage of electric needs. A closer look at the Gross Solar
Potential map for Hopkins suggests several high impact sites including SUPERVALU, the City’s
landfill as well as other large industrial sites. The report also examines Hopkins’ wind and
biomass resources and finds they would likely have less of an impact than solar.
Legal Authority. Zoning Code amendments are legislative actions in that the City is creating
new standards to regulate the development of certain types of uses and/or structures. Under the
law, the City has wide flexibility to create standards that will ensure the type of development it
desires; however, zoning regulations must be reasonable and supported by a rational basis
relating to promoting the public health, safety and welfare. Staff finds the proposed zoning
changes reasonable and supported by the existing Comprehensive Plan, initial findings from the
process to update the comprehensive plan and the City Council’s 2018 Goals and Strategic Plan.
Planning Report 17-08-TA
Page 3
Proposed Zoning Changes. Based on information from the SolSmart program, the City’s
sustainability goals, existing energy conditions in Hopkins and research on solar energy systems
standards in other communities, staff has prepared the attached draft Solar Energy Systems
ordinance for consideration. The ordinance is based on the Minnesota Model Solar Ordinance
but has been modified to address specific needs and conditions in Hopkins (see attached). The
draft ordinance includes the following sections.
Subdivision 1 - Purpose & Intent. This section details the rationale for the ordinance and what
it intends to accomplish.
Subdivision 2 - Definitions. This section details the specific terms and meanings associated with
the Solar Energy Systems.
Subdivision 3 - Allowable Uses. Solar energy systems are allowed as an accessory use in various
zoning districts throughout the city. Roof Mounted Solar Energy Systems are a permitted
accessory use in all zoning districts. Ground Mounted Solar Energy Systems part of a Solar
Farms or Solar Gardens are limited to the Closed Landfill Restricted District and require a
conditional use permit.
Subdivision 4 - Performance Standards. This section contains performance standards for height,
setback, visibility, coverage, system certification, utility connection, abandonment and
compliance with other codes.
Subdivision 5 - Review Process & Materials. This section details the review process for solar
energy systems. Roof Mounted Solar Energy Systems that meet the design requirements of the
ordinance will be granted administrative approval by the Zoning Official and not require
Planning & Zoning Commission review or City Council Approval. Roof Mounted Solar
Gardens or Ground Mounted Solar Energy Systems part of a Solar Farms require a conditional
use permit with review by the Planning & Zoning Commission and approval by the City
Council. Planning approval does not indicate compliance with Building Code or Electric Code.
Subdivision 6 - Conditional Use Permit. Deviation from the required standards of this section
may be allowed through a conditional use permit, provided that requests to reduce minimum
setback require a variance. In granting a conditional use permit, the city council shall consider
the criteria unique to solar energy systems.
Subdivision 7 - Restrictions on Solar Energy Systems Limited. As of (adoption date for this
ordinance) new homeowners’ agreements, covenant, common interest community standards, or
other contract between multiple property owners within a subdivision of Hopkins shall not
restrict or limit solar energy systems to a greater extent than Hopkins solar energy standards.
Subdivision 8 - Solar Access. The City of Hopkins encourages protection of solar access. Solar
access easements may be filed consistent with Minnesota State Statute 500.30. Any property
owner can purchase an easement across neighboring properties to protect access to sunlight.
The easement can apply to buildings, trees, or other structures that would diminish solar access.
CITY OF HOPKINS
Hennepin County, Minnesota
PLANNING AND ZONING COMMISSION RESOLUTION NO. 2018-02
A RESOLUTION MAKING FINDINGS OF FACT AND RECOMMENDING THE CITY
COUNCIL APPROVE AN ORDINANCE AMENDING THE ZONING ORDINANCE
RELATED TO SOLAR ENERGY SYSTEMS
WHEREAS, the City of Hopkins initiated an application to amend the Zoning Ordinance related to
Solar Energy Systems; and
WHEREAS, the procedural history of the application is as follows:
1. The Hopkins Planning & Zoning Commission reviewed the SolSmart Program during their
July and August 2017 meetings; and
2. That the Hopkins City Council reviewed and discussed this item during their September 5,
2017 meeting; and
3. That an application to amend the Zoning Ordinance related to Solar Energy Systems was
initiated by the City of Hopkins on December 22, 2017; and
4. That the Hopkins Planning & Zoning Commission review and heard presentations on such
application during the January 23 and February 27, 2018 meetings; and
5. That the Hopkins Planning & Zoning Commission, pursuant to published notice, held a
public hearing to review such application on March 27, 2018 and all persons present were
given an opportunity to be heard; and
6. That during the March 27th meeting, the Hopkins Planning & Zoning Commission voted to
table this item until their April 24, 2018 meeting to allow more time for study ; and
7. That the Hopkins Planning & Zoning Commission, continued the public hearing to review
such application on April 24, 2018 and all persons present were given an opportunity to be
heard; and
8. That written comments and analysis of City staff were considered.
NOW, THEREFORE, BE IT RESOLVED that an application to amend the Zoning Ordinance
related to Solar Energy Systems is hereby recommended for approval based on the following Findings of
Fact:
1. The proposed zoning ordinance text amendment is consistent with the existing Comprehensive
Plan, initial findings from the process to update the comprehensive plan, the City Council’s 2018
Goals and Strategic Plan and will protect the health, safety and general welfare of Hopkins.
Adopted this 24th day of April 2018.
______________________
Brian Hunke, Chair
520.10 – Solar Energy Systems
Subdivision 1. Purpose & Intent. It is the goal of the city council, as expressed in the
comprehensive plan, for Hopkins to become a more sustainable community by encouraging
activities that conserve energy and result in less/no pollution. In accordance with this objective, the
city finds that it is in the public interest to encourage the safe, effective and efficient use of
alternative energy systems that have a positive impact on energy production and conservation while
not having an adverse impact on the community. Therefore, the purposes of this section include:
Implement the solar resource protection element required under the Metropolitan Land
Planning Act by promoting rather than restrict development of alternative energy sources,
removing regulatory barriers and creating a clear regulatory path for approving alternative energy
systems.
To create a livable community where development incorporates sustainable design elements
such as resource and energy conservation and use of renewable energy.
Protect and enhance the environment, limit the effects of climate change and decrease the use of
fossil fuels.
To encourage alternative energy development in locations where the technology is viable and
environmental, economic and social impacts can be mitigated.
Support additional energy choice for consumers and promote competition in the electricity and
natural gas supply market.
Subdivision 2. Definitions. The following word, terms, and phrases, when used in this title, shall
have the meanings ascribed to them in this section:
COMMUNITY SOLAR GARDEN (SOLAR GARDEN): A solar-electric (photovoltaic) array that
provides retail electric power (or a financial proxy for retail power) to multiple community members
or businesses residing or located off-site from the location of the solar energy system, consistent
with Minn. Statutes 216B.1641 or successor statute.
RENEWABLE ENERGY EASEMENT, SOLAR ENERGY EASEMENT: An easement that
limits the height or location, or both, of permissible development on the burdened land in terms of
a structure or vegetation, or both, for the purpose of providing access for the benefited land to wind
or sunlight passing over the burdened land, as defined in Minn. Stat. 500.30 Subd. 3 or most recent
version.
RENEWABLE ENERGY SYSTEM: A solar energy or wind energy system. Renewable energy
systems do not include passive systems that serve a dual function, such as a greenhouse or window.
ROOF PITCH: The final exterior slope of a building roof calculated by the rise over the run,
typically but not exclusively expressed in twelfths such as 3/12, 9/12, 12/12.
SOLAR ACCESS: Unobstructed access to direct sunlight on a lot or building through the entire
year, including access across adjacent parcel air rights, for the purpose of capturing direct sunlight to
operate a solar energy system.
SOLAR COLLECTOR: A device, structure or a part of a device or structure for which the primary
purpose is to transform solar radiant energy into thermal, mechanical, chemical, or electrical energy.
SOLAR COLLECTOR SURFACE: Any part of a solar collector that absorbs solar energy for use
in the collector’s energy transformation process. Collector surface does not include frames, supports
and mounting hardware.
SOLAR DAYLIGHTING: A device specifically designed to capture and redirect the visible portion
of the solar spectrum, while controlling the infrared portion, for use in illuminating interior building
spaces in lieu of artificial lighting.
SOLAR ENERGY: Radiant energy received from the sun that can be collected in the form of heat
or light by a solar collector.
SOLAR ENERGY SYSTEM: A device or structure design feature, the substantial purpose of
which is to provide daylight for interior lighting or provide for the collection, storage and
distribution of solar energy for space heating or cooling, electricity generation, or water heating.
SOLAR ENERGY SYSTEM, ACTIVE: A solar energy system whose primary purpose is to
harvest energy by transferring solar energy into another form of energy or transferring heat from
a solar collector to another medium using mechanical, electrical, or chemical means.
SOLAR ENERGY SYSTEM, BUILDING INTEGRATED: A solar energy system that is an
integral part of a principal or accessory building, rather than a separate mechanical device, replacing
or substituting for an architectural or structural component of the building. Building-integrated
systems include but are not limited to photovoltaic or hot water solar energy systems that are
contained within roofing materials, windows, skylights, and awnings.
SOLAR ENERGY SYSTEM, GRID INTERTIE: A photovoltaic solar energy system that is
connected to an electric circuit served by an electric utility company.
SOLAR ENERGY SYSTEM, GROUND MOUNTED: A freestanding solar system mounted
directly to the ground using a rack or pole rather than being mounted on a building.
SOLAR ENERGY SYSTEM, OFF GRID: A photovoltaic solar energy system in which the circuits
energized by the solar energy system are not electrically connected in any way to electric circuits that
are served by an electric utility company.
SOLAR ENERGY SYSTEM, PASSIVE: A system that captures solar light or heat without
transforming it to another form of energy or transferring the energy via a heat exchanger.
SOLAR ENERGY SYSTEM, PHOTOVOLTAIC: A solar energy system that converts solar energy
directly into electricity.
SOLAR ENERGY SYSTEM, ROOF MOUNTED: A solar energy system mounted on a rack that
is fastened to or ballasted on the roof of a principal or accessory building.
SOLAR FARM: A commercial facility that converts sunlight into electricity, whether by
photovoltaics (PV), concentrating solar thermal devices (CST), or other conversion technology, for
the primary purpose of wholesale sales of generated electricity.
SOLAR HEAT EXCHANGER: A component of a solar energy device that is used to transfer heat
from one substance to another, either liquid or gas.
SOLAR HOT AIR SYSTEM: (also referred to as Solar Air Heat or Solar Furnace) – A solar energy
system that includes a solar collector to provide direct supplemental space heating by heating and re-
circulating conditioned building air. The most efficient performance typically uses a vertically
mounted collector on a south-facing wall.
SOLAR HOT WATER SYSTEM: A system that includes a solar collector and a heat exchanger
that heats or preheats water for building heating systems or other hot water needs, including
residential domestic hot water and hot water for commercial processes.
SOLAR MOUNTING DEVICES: Racking, frames, or other devices that allow the mounting of a
solar collector onto a roof surface or the ground.
SOLAR RESOURCE: A view of the sun from a specific point on a lot or building that is not
obscured by any vegetation, building, or object for a minimum of four hours between the hours of
9:00 AM and 3:00 PM Standard time on all days of the year.
Subdivision 3. Allowable Uses. Solar energy systems shall be allowed as an accessory use in
various zoning districts throughout the city as prescribed below. Solar Farms or Solar Gardens shall
require a conditional use permit as prescribed in Section 525.13 (Conditional Use Permit).
A. Roof Mounted Solar Energy Systems are a permitted accessory use in all zoning districts.
B. Roof Mounted Solar Gardens are a conditional accessory use in all nonresidential districts.
C. Ground Mounted Solar Farms or Solar Gardens are a conditional accessory uses in the Closed
Landfill Restricted District, subject to:
1. Conformance with the standards of the Closed Landfill Restricted District.
2. Stormwater. Solar farms are subject to the City’s stormwater management and erosion and
sediment control provisions and National Pollutant Discharge Elimination System (NPDES)
permit requirements.
3. Ground Cover and Buffer Areas. The following provisions shall be met related to the
clearing of existing vegetation and establishment of vegetated ground cover. Additional
requirements may apply as required by the City.
a. The project site design shall include the installation and establishment of ground cover
meeting the beneficial habitat standard consistent with Minnesota Statutes, Section
216B.1642, or successor statutes and guidance as set by the Minnesota Board of Water
and Soil Resources.
b. Beneficial habitat standards shall be maintained on the site for the duration of operation,
until the site is decommissioned.
c. The applicant shall submit a financial guarantee in the form of a letter of credit, or other
form acceptable to the City Attorney equal to one hundred twenty-five (125) percent of
the costs to meet the beneficial habitat standard. The financial guarantee shall remain in
effect until vegetation is sufficiently established.
4. Foundations. A qualified engineer shall certify that the foundation and design of the solar
panels racking and support is within accepted professional standards, given local soil and
climate conditions.
5. Power and Communication Lines. Power and communication lines running between banks
of solar panels and to nearby electric substations or interconnections with buildings shall be
buried underground. Exemptions may be granted by the City in instances where shallow
bedrock, water courses, or other elements of the natural landscape interfere with the ability
to bury lines, or distance makes undergrounding infeasible, at the discretion of the zoning
administrator.
6. Aviation Protection. For solar farms located within 500 feet of an airport or within
approach zones of an airport, the applicant must complete and provide the results of the
Solar Glare Hazard Analysis Tool (SGHAT) for the Airport Traffic Control Tower cab and
final approach paths, consistent with the Interim Policy, FAA Review of Solar Energy
Projects on Federally Obligated Airports, or most recent version adopted by the FAA.
7. Decommissioning. A decommissioning plan shall be required to ensure that facilities are
properly removed after their useful life. Decommissioning of solar panels must occur in the
event they are not in use for 12 consecutive months. The plan may include provisions for
removal of all structures and foundations, restoration of soil and vegetation and a plan
ensuring financial resources will be available to fully decommission the site. The City may
require the posting of a bond, letter of credit or the establishment of an escrow account to
ensure proper decommissioning.
Subdivision 4. Performance Standards
A. Height. Solar energy systems shall comply with the following height requirements:
1. Roof Mounted Solar Energy Systems shall comply with the height standards of the
applicable zoning district.
2. Ground Mounted Solar Energy Systems part of a Solar Farms or Solar Garden shall not
exceed fifteen feet (15') in height when oriented at maximum tilt.
B. Setback. Solar energy systems shall comply with the following setback requirement.
1. Roof Mounted Solar Energy Systems shall comply with the setbacks requirement for the
applicable zoning district and structure type (principal or accessory) on which they are
mounted.
2. Ground Mounted Solar Energy Systems part of a Solar Farms or Solar Garden shall comply
with the principal front yard setback requirements of the abutting zoning district.
3. Setback encroachments shall be permitted as allowed under Section 520.09, Subdivision 2.a
(Not Encroachments) provide the applicant demonstrates the collector and mounting
system has been explicitly engineered to safely extend beyond the roof edge
C. Visibility. Solar energy systems shall be designed to blend into their surroundings or the
architecture of the associated building provided mitigating for visual impacts will allow the
system to function within expected industry standards. The color of the solar collector is not
required to be consistent with other roofing materials.
1. Pitched Roofs. Systems mount on pitched roofs that are visible from the nearest edge of the
right-of-way, other than an alley, shall not have a highest finished pitch steeper than the roof
pitch on which the system is mounted and shall be no higher than ten (10) inches above the
roof.
2. Flat Roofs. System mounted on flat roof may be attached at an angle to improve their
efficiency, provided the highest point of a solar panel is not visible from the nearest edge of
the public right-of-way, other than an alley.
3. Ground Mounted Solar Energy Systems. Ground Mounted Solar Energy Systems part of a
Solar Farm or Solar Gardens and visible from the public right-of-way shall include buffering
features such as setback, berming, landscaping, fences, walls or a combination thereof to
soften the appearance of the system and improve visual aesthetics.
4. Reflectors. All solar energy systems using a reflector to enhance solar production shall
minimize glare from the reflector affecting adjacent or nearby properties. Measures to
minimize glare include selective placement of the system, screening on the north side of the
solar array, modifying the orientation of the system, reducing use of the reflector system, or
other remedies that limit glare.
D. Coverage. Roof Mounted Solar Energy Systems, excluding building-integrated systems, shall
allow for adequate roof access for fire-fighting purposes to the south-facing or flat roof upon
which the panels are mounted. Ground-mount systems shall be exempt from building coverage
standards if the soil under the collector is not compacted and maintained in vegetation.
Foundations, gravel, or compacted soils are considered impervious.
E. Certifications. Solar electric system components shall be certified by Underwriters Laboratories,
Inc., and solar thermal systems shall be certified by the Solar Rating and Certification
Corporation, or other appropriate certification(s) as determined by the city. The city reserves
the right to deny a building permit for proposed solar energy systems deemed to have
inadequate certification.
F. Compliance with Building Code. All solar energy systems shall meet approval of Building
Officials, consistent with the State of Minnesota Building Code, and solar thermal systems shall
comply with HVAC-related requirements of the Energy Code.
G. Compliance with State Electric Code. All photovoltaic systems shall comply with the Minnesota
State Electric Code.
H. Compliance with State Plumbing Code. Solar thermal systems shall comply with applicable
Minnesota State Plumbing Code requirements.
I. Utility Connection: All grid intertie systems shall have an agreement with the local utility prior to
the issuance of a building permit. A visible external disconnect must be provided if required by
the utility. Off grid systems are exempt from this requirement.
J. Abandonment. If the solar energy system remains nonfunctional or inoperative for a
continuous period of one year, the system shall be deemed to be abandoned and shall constitute
a public nuisance. The owner shall remove the abandoned system at their expense after a
demolition permit has been obtained. Removal includes the entire structure including
transmission equipment.
Subdivision 5. Review Process & Materials. Except as provided below, no solar energy system
shall be erected, altered, improved, reconstructed, maintained or moved in the city without first
securing a permit from the city. Roof Mounted Solar Energy Systems that meet the design
requirements of this ordinance shall be granted administrative approval by the Zoning Official and
shall not require Planning & Zoning Commission review or City Council Approval. Roof Mounted
Solar Gardens or Solar Farms shall require a conditional use permit as prescribed under Section Plan
525.13. Planning approval does not indicate compliance with Building Code or Electric Code.
A. Exemptions. The following solar energy systems are exempt from the requirements of this
section.
1. Passive and building integrated systems. These systems shall be regulated as any other
building element.
2. Solar energy collector devices less than one (1) square foot in area and generally used for
garden decoration, exterior accent lighting for residential homes, lawns, and flagpoles.
3. Accessory systems installed by a government agency on light poles, signs, transit shelters or
within public right-of-way.
B. Elevation Drawings Required. All solar energy system applications shall include horizontal and
vertical building elevation draw at an Architects scale. The drawings must show the location of
the system on the building and the applicable information detailed below.
1. Pitched Roof Mounted Solar Energy Systems. The drawings shall show the highest finished
slope of the solar collector and the slope of the finished roof surface on which it is mounted.
2. Flat Roof Mounted Solar Energy Systems. The drawings must shows the distance to the
roof edge and any parapets on the building. They shall also identify the height of the
building on the street frontage side, the shortest distance of the system from the street
frontage edge of the building, and the highest finished height of the solar collector above the
finished surface of the roof.
C. Site Plan Required. All solar energy system applications shall include site plan drawn at an
Engineer’s scale. The site plan must show the location of all solar arrays, other structures,
property lines, rights-of-way, service roads, floodplains, wetlands and other protected natural
resources, topography, electric equipment, and all other characteristics requested by City.
Subdivision 6. Conditional Use Permit. Deviation from the required standards of this section
may be allowed through a conditional use permit in accordance with Section 525.13 provided that
request to reduce minimum setback requirements shall be by variance. In granting a conditional use
permit, the city council shall consider the criteria in said Section 525.13 of this title and the following
additional criteria unique to solar energy systems:
A. That the deviation is required to allow for the improved operation of the Solar Energy System.
B. That the Solar Energy System has a net energy gain.
C. That the Solar Energy System does not adversely affect solar access to adjacent properties.
D. That the Solar Energy System complies with all other engineering, building, safety and fire
regulations; and
E. That the Solar Energy System is found to not adversely impacts on the surrounding area,
including the health, safety and general welfare of occupants of neighboring properties and users
of public rights of way.
Subdivision 7. Restrictions on Solar Energy Systems Limited. As of (adoption date for this
ordinance) new homeowners’ agreements, covenant, common interest community standards, or
other contract between multiple property owners within a subdivision of Hopkins shall not restrict
or limit solar energy systems to a greater extent than Hopkins solar energy standards.
Subdivision 8. Solar Access. The City of Hopkins encourages protection of solar access. Solar
access easements may be filed consistent with Minnesota State Statute 500.30. Any property owner
can purchase an easement across neighboring properties to protect access to sunlight. The easement
can apply to buildings, trees, or other structures that would diminish solar access.
EXISTING ENERGY CONDITIONS
CITY OF HOPKINS
OCTOBER 2017
Prepared by:
Great Plains Institute
The development of this guide is supported by the Department of Energy, Office of Energy
Efficiency and Renewable Energy (EERE), under Award Number DE- DE-EE0007229. This project
was made possible by a grant from the U.S. Department of Energy and the Minnesota
Department of Commerce. The team includes LHB, Great Plains Institute, and the University of Minnesota’s Energy Transition Lab and
Center for Science, Technology, and Environmental Policy.
Hopkins Existing Energy Conditions 2
EXISTING ENERGY CONDITIONS: HOPKINS
Hopkins is a Step 3 GreenStep City and is committed to building a sustainable community. The city is interested
in better understanding how energy is consumed in its community so it can implement strategies to reduce
energy consumption and increase clean energy production, and to reduce greenhouse gas (GHG) emissions from
buildings and transportation. The information for this report includes data from the Regional Indicators Initiative
(2013) and Xcel Energy’s Community Energy Reports (2016).
Energy Use Profile
Businesses and residents in Hopkins are served by Xcel
Energy for electricity and CenterPoint Energy for natural
gas. The types of energy used in Hopkins for buildings
and industrial processes are primarily electricity and
natural gas. Few residents may use heating fuel, biomass,
or propane as their primary heating source, but that is
not captured in this report. Figure 1 demonstrates that
consumers use more natural gas than electricity, with
60% of the energy consumed in buildings coming from
natural gas. Natural gas is primarily used for space and
water heating, cooking, and various industrial processes.
Electricity is used for appliances, water and space heating,
space cooling, lighting, commercial and industrial
processes, as well as other electronic devices. Figure 2
illustrates that commercial consumers use a greater
share of total energy than residential consumers. The
commercial sector makes up 71% of total commercial
energy use (natural gas and electricity).
According to the Community Energy Report from Xcel
Energy, Hopkins residents and businesses spent $20.8
million on electricity in 2016; an average of $771 per
household, $4,975 per commercial customer, and
$43,830 per industrial customer. This information is not
available for natural gas use at this time. According to the
Energy Information Administration, Minnesota households
spent $1,108 on electricity in 2015, and Minnesota
businesses spent $7,585, on average.
Figure 2 Data Source: 2013 Regional Indicators Initiative Report,
2016 Community Energy Report from Xcel Energy
29%
71%
Energy Use by Sector (MMBtu)
Total Residential Total Commercial
Figure 1 Data Source: 2013 Regional Indicators Initiative Report,
2016 Community Energy Report from Xcel Energy
Total
Electricity
40%
Total
Natural Gas
60%
Energy Use by Type (MMBtu)
Total Electricity Total Natural Gas
Hopkins Existing Energy Conditions 3
There are 8,290 residential customers and 1,152 commercial customers in Hopkins. Consumption of natural gas
has largely remained steady between 2007 and
2013. As mentioned, natural gas is the primary fuel
for space heating. In Minnesota, it is especially
important to have reliable and affordable heating
systems. Inefficient homes and high energy costs
have a greater impact on low- and moderate-income
residents who are less able to respond to such
changes and bear a greater energy burden (energy
costs as a percentage of total income) than higher
income residents.
Greenhouse gases (GHG) are emitted from burning
conventional fuels like coal and natural gas, which
are both inputs in the production of electricity. GHGs
are also emitted from burning natural gas, propane, or
fuel oil for the purpose of space and water
heating, as well as cooking and other uses.
Figure 4 indicates that the greatest source of
GHG emissions from all buildings (commercial
and residential) in Hopkins (57%) come from
consumption of electricity as compared to
heating fuels.
Using carbon free (wind and solar) or carbon-
neutral (biomass) energy sources and
investing in energy efficiency can significantly
reduce the amount of greenhouse gases that
are attributable to building energy use.
Hopkins’ electric energy supply is getting
cleaner as Xcel Energy adds more clean energy
each year. Developing local clean energy capacity for
homes and businesses, or through mechanisms such
as community shared solar systems, is an alternative to a supply-side effort.
The commercial sector makes up 72% of the of the GHGs emitted from building energy use. Because there are
fewer business customers, there is greater opportunity to reduce GHG emissions among fewer large commercial
customers than there is residential. Much of those emissions are from industrial processes.
Figure 4 Data Source: 2013 Regional Indicators Initiative Report
-
2,000,000
4,000,000
6,000,000
8,000,000
10,000,000
12,000,000
2007 2008 2009 2010 2011 2012 2013
Natural Gas Usage
Residential Service Gas Commercial/Industrial Gas
Total
Electricity,
72,809 , 57%
Total Natural
Gas, 54,938 ,
43%
Greenhouse Gas Emissions by Energy Type
Total Electricity Total Natural Gas
Figure 3 Source: CenterPoint Energy
Hopkins Existing Energy Conditions 4
Transportation Energy Use Profile
Transportation energy is almost exclusively attributable to car and truck travel, and is estimated by the vehicle
miles traveled (VMT) within the city boundaries (regardless of through traffic or with an origin or destination in
the city).
The VMT includes commercial and freight vehicles, personal cars, and mass transit vehicles. VMT does not
capture energy attributable to rail and airplanes, but those are generally a very small portion of transportation
energy. Regional Indicators Initiative data shows that 93,604,485 vehicle miles were traveled within Hopkins in
2014. The greenhouse gas emissions associated with this travel is approximately 41,794 tonnes of CO2e, or
about 25% the city’s total GHG emissions. The U.S. Department of Energy reports that there are 15,500 light
duty vehicles in the Hopkins market with an average fuel economy 23.4 miles per gallon. 90% of these vehicles
use gasoline as the primary fuel; flex fuel (e85) makes up the next highest fuel source.
Figure 5 Data Source: https://apps1.eere.energy.gov/sled/#/
90%
Unknown
Hybrid
Diesel/Biodiesel
Flex Fuel
10%
Hopkins Light Duty Passenger Vehicle Fuel Type
Gasoline Unknown Hybrid Diesel/Biodiesel Flex Fuel
Hopkins Existing Energy Conditions 5
Greenhouse Gas Emissions Summary
The energy use data gathered for building energy consumption and transportation illustrate a clear picture of
the major sources of GHG emissions in the community, as seen in Figure 6. The largest share of emissions come
from residential and commercial (buildings) energy consumption, making up 75% of total emissions. Broken
down by sector, residential energy use accounts for 21% of emissions, while the commercial sector emits 54% of
all emissions. Transportation makes up 25% of total emissions.
Additional sources of emissions not included in this graph are those associated with regional facilities such as air
travel, solid waste, and wastewater treatment. While these sources are significantly smaller than those
evaluated in this report, a GHG inventory that meets the U.S. community protocol or the Global Protocol would
consider these emissions. The city can determine whether to conduct the additional analysis to be compliant
with the protocol as part of a deeper GHG inventory.
Transportation,
41,794 , 25%
Residential,
35,238 , 21%
Commercial,
92,509 , 54%
GHG Breakdown (Tons of CO2)
Transportation Residential Commercial
Figure 6 Data Source: 2013 Regional Indicators Initiative Report
Hopkins Existing Energy Conditions 6
Efficiency Resource
The city’s efficiency resource is measured by looking at current energy use. The greater the energy consumption,
the greater resource available for Hopkins to be more efficient. As noted in the energy use profile, the energy
use - and therefore the efficiency resource - is largest in businesses as compared to households. Energy use in
the commercial and industrial sector is 55% of the city’s total building energy use. Further, electricity is a greater
use among businesses, while heating fuels dominant residential energy use. It is also important to note that
while commercial buildings consume a majority of the energy, they comprise only 20% of the square footage,
and represent little over 10% of the number of buildings in the community.
Focusing on commercial and industrial building energy use is a potentially high-impact strategy for capturing the
city’s efficiency resource; a single successful efficiency investment could reap the efficiency benefits of dozens of
residential successes. Residential building efficiency opportunities tend to be more standardized than
commercial use, even if the efficiency resource is distributed across many buildings rather than being
concentrated in relatively few. Residential efficiency opportunities are in building envelopes, heating and cooling
equipment, lighting, appliances, and plug loads. These uses have efficiency solutions that do not need to be
customized, and can reduce typical residential household use by 20-25%.
Xcel Energy offers incentives to residential and business customers to help increase energy efficiency action.
Participation rates for these programs can be found in the Community Energy Reports. For Hopkins, 2016
participation rates by businesses and residents were:
Table 1 Participants in Xcel Energy’s rebate program
Sector Rebates Given Electricity Savings (kWh)
Business 46 2,688,030
Residential 139 93,763
Table 1 Xcel Energy's rebate program summary
Fuel (MMBtu)
Fuel (MMBtu)
Fuel (MMBtu)
Electricity
(MMBtu)
Electricity
(MMBtu)
-
200,000
400,000
600,000
800,000
1,000,000
1,200,000
1,400,000
Residential Commercial Transportation
Energy Efficiency Potential
Figure 7 Source: RII 2013, and Xcel CER 2016
Hopkins Existing Energy Conditions 7
Transportation efficiency is another significant resource, as travel comprises 25% of the city’s GHG emissions.
GHG emissions can be reduced with three distinct strategies:
1) fuel switching to a low-carbon or carbon-free fuel;
2) improved efficiency (miles per gallon) or right-sizing vehicles to the vehicle use;
3) mode shifting, or increased use of non-motorized or transit options.
Electric vehicle markets are poised for rapid expansion over the next decade and the city has opportunities to
accelerate market transformation and reduce GHG emissions associated with transportation fuels and vehicle
use. For example, including EVs in city fleets, investing in public charging stations, and promoting EV benefits can
help drive consumers to choose electric vehicles.
Improved efficiency in vehicles is likely to occur via increased use of hybrid models. These still burn gasoline, but
have long-ranges and now come in a variety of vehicle types used by residents and businesses.
Hopkins is already well attuned to creating opportunities for mode-shifting, particularly related to creating
pedestrian and bicycle friendly transportation infrastructure and urban design. There will be additional
opportunities for the city to expand transit-oriented development as Metro Transit expands light rail service
through the community.
Hopkins Existing Energy Conditions 8
Solar Resource
The University of Minnesota developed a high-resolution statewide solar resource map that allows cities to
calculate how much electricity they could potentially receive from locally installed solar energy systems. These
data (see map, next page) were used to calculate Hopkins’ solar resource, or the city’s “solar reserves.” The solar
reserves are how much solar energy is reasonably economically available for development, similar to how oil or
gas reserves are measured. The solar map shows the good sites for solar installations and helps identify where
there may be land use conflicts with solar development. Table 2, below, shows the amount of solar energy
reasonably available for development in Hopkins. The gross potential includes the total available resource,
regardless of location; rooftop capacity and generation include only the resource available on the rooftops of
commercial buildings located in the city.
Table 2. Hopkins Rooftop Solar Resource
The total capacity of the commercial rooftop solar resource in Hopkins is 86 MW, equal to approximately 55% of
all the electricity consumed in the city. This means that if the city wanted to maximize its entire commercial
rooftop solar resource, it could set a solar generation goal of up to 55% on-site solar generation (this is an upper
limit, and does not consider individual site
limitations due to roof structure,
ownership, or local regulations that might
limit solar installations). If buildings
undergo high levels of energy efficiency
investment, the solar resource could meet
a higher percentage of electric needs. The
efficiency and solar resources are, in this
analysis, calculated independently of each
other.
Solar installations are not limited to
rooftop applications. This analysis does not
include ground-mount systems, but the city
will want to develop criteria for where they
would and would not allow solar installations. For instance, commercial parking lots may make good solar
resources, or public right of ways; while areas planned for future development or park space may not. These
criteria can be used to recalculate potential solar generation and redefine future solar goals for local
development.
Community Total Generation
Potential
Rooftop Generation
Potential Rooftop Capacity Top 10 Rooftop
Potential
Hopkins 5,402,574 MWh/year 111,590 MWh/year 86 MW 30,195 MWh/year
Figure 6 Example of Solar Potential and Community Goal
1.5%
10%
25%
0
20,000
40,000
60,000
80,000
100,000
120,000
Total Rooftop Top 10 buildings Local
Government
Goal
Solar Generation Potential (MWh/yr)
Figure 8 City of Hopkins solar generation potential
Hopkins Existing Energy Conditions 9
Hopkins Existing Energy Conditions 10
Wind Resource
Hopkins is a suburban community with small town characteristics and varying suitability for towers above a
certain height. The Minnesota Department of Commerce developed wind speed maps at a 500-meter resolution
to give a general sense of the wind resource at various tower heights, these are not adequate for a specific site
assessment (Figure 8).
Figure 10 Wind speeds at different tower heights, 30 meters, 80 meters, and 100 meters from left to right. Source: MN Department of
Commerce
A good rule of thumb is that 12 mph is typically the minimum average annual wind speed for a good wind
resource. At 30 meters, much of Hopkins has an average wind speed of less than 9 miles per hour, below the
optimal speed needed for a productive wind energy system, suggesting that taller towers would be necessary
from a production standpoint. At 80 meters, wind speeds are between 11 and 13 mph, and at 100 meters, wind
speeds are up to 13-15 mph. While there may be some opportunity to capture the resource at taller tower
heights, it may not be feasible in Hopkins. The taller towers would require deeper foundation, which may not
work in areas where the water table is too high. Additionally, the community may run into resistance if residents
do not agree that tall wind turbines fit the community’s character.
While the city does not have many opportunities for wind energy development, residents and businesses can
participate in Xcel Energy’s Windsource® or Renewable*Connect programs. These programs provide the clean
Wind Resource
A good wind energy site needs to meet a number of characteristics, the most important of which is a good
wind resource. Other characteristics include soils that can support the weight of the turbine; a site large
enough to accommodate safety setbacks from neighboring properties, structures, or other uses; and
surrounding land uses for which the visual impact and potential nuisances will not create a conflict.
Regarding the wind resource, the height the rotor needs to be above any disturbance within an ideal radius
of 500 feet. The Distributed Wind Energy Association offers this guidance:
The industry guidance on minimum wind turbine height states that the lowest extension of a wind turbine
rotor must be 60 feet above the ground, assuming no surrounding obstacles. Where obstacles are present, the
wind turbine rotor should be at least 30 feet above the tallest obstacle within a 500 -foot radius. If trees are not
fully grown, then the tower height must be adjusted for the growth over the next two or so decade s, the life of
the wind turbine.
Figure 9 Solar Resource Map, Metropolitan Council Community Page
Hopkins Existing Energy Conditions 11
energy benefit of having local wind (and solar) energy, although the economic benefits of clean energy
development are realized elsewhere. According to Xcel Energy, two businesses are subscribed to a total of
16,207 kWh of wind energy, 296 residences are subscribed to a total of 609,390 kWh of wind energy.
Hopkins Existing Energy Conditions 12
Biomass Resource
Fuel derived from biomass can be used in several processes as a source of renewable energy, including
electricity, waste heat, and renewable gas. Minnesota has several facilities that use biomass to generate
electricity and/or heat. Biomass resources include municipal solid waste, landfill gas, wood waste, and
agricultural byproducts, food processing residue and other organic waste. Much of the biomass resource can
come from the metropolitan area, particularly for solid waste and landfill gas, as well as yard and urban forest
waste.
Information about the type of biomass resources at the community level is difficult to acquire; there is little
standardized assessment of potential biomass resources, and the types of resources vary across communities.
All of the refuse that is not recycled or composted in Hopkins goes to one of two waste-to-energy facilities:
Hennepin Energy Resource Company or NRG Elk River (NSP) Resource Recovery. In its draft master solid waste
management plan, Hennepin County seeks to expand organics recycling by adding capacity to receive, transfer,
and process organics close to where the materials are generated and collected. Organic materials are the largest
portion of trash, making up approximately 25% of the waste stream. As part of its strategies, the County will
release a request for proposals for an anaerobic digestion project to be in operation no later than the end of
2022. The County is looking at technologies to create renewable, bio-based energy and green chemicals.
Biomass as Renewable Energy
Anaerobic digestion is a process that uses captured biogas (methane and carbon dioxide) from the
decomposition of organic material to generate heat and/or electricity. Biogas generated from this process
can also be cleaned to remove carbon dioxide and other impurities to produce a renewable product
equivalent to conventional natural gas, referred to as renewable natural gas. Renewable natural gas (or
biogas) can serve as a replacement for any natural gas application and can also be compressed to provide a
source of transportation fuel in place of conventional natural gas.
Biogas can be used to generate electricity in a process called combined heat and power. Combined heat and
power (CHP) systems simultaneously generate electricity and thermal energy within a single system. By
using the thermal energy, CHP systems efficiency is much greater than conventional power generating
systems. While this system is well established in Minnesota, there is still great potential to harness this
resource. Benefits CHP application include:
• Power is produced at a cost below retail electricity
• Enhance local power reliability
• Produces more useful energy than biogas that is used solely for thermal loads
• Reduces greenhouse gas emissions and other air pollutants