Johnson House
Solar Panel Feasibility Analysis:
Locations, Costs, and Benefits
Prepared by:
Manya Gordon
Kendall McElroy
Oliver Scofield
Ashley Reese
April 28, 2014
Executive Summary
We believe that the Johnson House - as part of the Gund Institute - would benefit from
the use of solar power and embody an exemplary model of renewable energy implementation on
the University of Vermont’s campus. Through our information collected during energy audits,
cost vs. benefit analyses and literature review, we investigated the feasibility of rooftop mounted
PV panels, ground mounted panels with solar tracking, and parking lot PV panels. We note that
our analysis was based from the data received regarding the 2011-2012 energy use of the
Johnson House: a total of 27,760 kWh. Hypothetically, 5 hours of sun exposure for a 5kW solar
panel system would produce 50 kWh a day and 18,250 kWh a year; these are the types of
benefits that we investigated based on optimum sun exposure and project costs. After
consideration from the Comprehensive Campus Renewable Energy Feasibility Study and our
own research, we conclude that carport mounted solar panels in nearby parking lots offer the
most promising locations for producing future renewable solar energy. We believe that
implementation of this project would be valuable in the Gund Institute’s ecological leadership on
campus.
Introduction
The Gund Institute for Ecological Economics, renowned internationally for its
contemporary scholarship regarding the research of “the interface of ecological, social, and
economic systems… [and search for] practical solutions to local and global environmental
challenges, and provid[ing] future leaders with the tools and understanding necessary to navigate
the transition to a sustainable society.” (Gund Institute Purpose Statement) At the forefront of
environmental challenges, we find the urgent need to shift our dependency on extracted fossil
fuels to that of renewable sources of efficient energy. Specifically, as we transition to a
sustainable and ecologically responsible Vermont, knowledge, production, and consistent critical
assessments of global strides in energy efficiency and renewable energy sources become critical,
especially if we hope to reflect a thorough understanding of ecosystem services in a postpetroleum future. The Gund Institute at the University of Vermont thus has the opportunity today
to lead by example in the promotion of an environmental university, in which pragmatic
application of sustainable solutions represents its simultaneous leadership in ecological
scholarship.
Although there are in fact many different sources of renewable energy technologies
already available developmentally (i.e. biofuels, hydropower, solar power, wind power,
geothermal, etc.), we focus today on the implementation of solar photovoltaic power generation
as arguably the most available source of renewable energy currently accessible to the Gund.
While the solar cell was developed in 1941 by Russel Ohl, the understanding of photo electric
light generation has only recently been widely understood. Research indicates that as photons
strike certain compounds, in particular a variety of specific metals, the surface of the material
emits electrons while the light that strikes other compounds will cause the material to accept
electrons. Known as the photo-electric effect, the combination of these two compounds can be
used to cause electrons to flow through a conductor, thereby creating electricity by a series of
flows of electrons.
It is important to note that although solar panels themselves can generate electricity
without any waste or pollution, the current extraction of the rare metals used in the development
(such as monocrystalline silicon, polycrystalline silicon, amorphous silicon, cadmium telluride or
copper indium selenide/sulfide) implicitly perpetuates our dependency on environmental
degradation. Futuristic advances in solar photovoltaic light will likely see incorporation of nonrare metals and other materials that do not require dangerous mining labor to acquire, perhaps
through the use of local plants and other biotic photo-synthesizers. However, in the face of the
urgency called upon by our society to transition away from petroleum-based energies,
contemporary solar PV technology offers a relatively safe, efficient, affordable, and – perhaps
most importantly – immediate alternative.
In the following report, we provide a feasibility study of implementing and constructing
solar panels for the Johnson House. Our study will convey information about the cost and
benefits of solar panel use. In addition, we will investigate how they could be implemented in
offsetting the building’s non-renewable energy use, as well as possible locations for the solar
panels that take into account any historical regulations for the property.
Methods
In order to develop our report, we obtained the Johnson House’s electricity bill; from
this, we were able to determine how much of its yearly electricity use would be covered by a
certain amount of solar panels. In addition, the first part of our methodology consisted of
literature review - historical building regulations, campus planning guidelines, pros and cons of
battery vs. on-the-grid solar power, Vermont tax incentives and existing feasibility studies. We
investigated solar panels in Burlington to understand different possible applications; we
focused on rooftop, rotating, and parking lot PV solar panels. Several bar graphs and data
collections indicating the energy production of these solar panels were available for us to utilize.
We interviewed Lani Ravin, UVM’s associate campus planner, to understand the process
of developing on campus and to learn from her expertise on past renewable energy research. She
provided us with the Comprehensive Campus Renewable Energy Feasibility Study, which we
built on to make a specific recommendation for the Johnson House; in addition, she provided us
with other campus planning guidelines and the UVM project request form to mold our
recommendations.
Discussion and Results
Tax Exemptions and Incentives
Important considerations in the discussion of localized solar energy also include the
various tax exemptions and incentives for which buildings and businesses qualify when solar
powered. Vermont is a forward-thinking state; already there are a number of tax incentives that
should be applicable to the Gund Institute. Some reduce the initial cost of the panels and
installation and some are tax related. Vermont’s largest incentive comes from the Vermont Small
Scale Renewable Energy Incentive; however, this may only be available if the panels are
installed by Vermont Solar Partners. It amounts to roughly 16% reduction of installation costs by
paying the customer 75 cents per watt generated by the system. While this is an example of a
larger incentive available and possibly applicable to the Gund, a much more complete and formal
list can be found online at the Database of State Incentives for Renewables and Efficiency.
(http://dsireusa.org/incentives/index.cfm?re=1&ee=1&spv=0&st=0&srp=1&state=VT)
Net Metering
A similar example of drawing savings and funding back through while operating grid
solar panels is by net metering. This means that should the Johnson House ever produce more
energy than it consumes on average, Burlington Electric will pay approximately 12 cents per
extra kWh back to the Gund, for use as credit on days when usage exceeds production. On top of
this, Vermont is starting to offer a program that further incentivizes residents and businesses to
install net metered solar by increasing the amount for which companies must give credit in the
production of extra available output energy to approximately 20 cents per kWh. This law, called
the Vermont Statewide Solar Adder, is still in progress but should be finalized by this summer.
Battery and “On the Grid” Solar Options
While the Johnson House going “off the grid” might outwardly seem to embody
sustainability, the action actually fosters harmful reductionism within the context of the greater
UVM. Solar panels that are tied into the grid are in fact more logical than a battery storage unit
for a number of reasons. First of all, the building is already connected to the grid, so using the
preexisting system decreases the need to produce and finance new technologies. Secondly, off-
grid solar panels use lead acid batteries. These batteries are filled with many toxins, and are
harmful to the environment and energy intensive to produce. Panels tied into the grid are
recommended to prevent excessive environmental degradation in those locations where an
efficient grid system already exists (like Burlington).
One benefit of battery, or “off the grid”, solar is that there are theoretically no power
outages. When one part of the grid goes down, all of it must be shut off to safely fix the problem,
including buildings with solar. This is not necessarily a problem for off-grid solar; however it is
important to keep in mind that off-grid solar installations with insufficient or inconsistent
sunshine and without huge battery storage space often need to supplement solar energy with a
generator. The grid has essentially unlimited storage capacity, and can also supplement solar on
cloudy days.
Thus remaining tied to the grid also makes sense for efficiently producing energy.
Transferring power from panels to batteries to useable electricity loses more energy than panels
in the grid. Incorporation in the grid also allows surplus energy to be used elsewhere in the grid,
whereas batteries simply cannot store very much surplus.
Holistic Sustainability at UVM
This supports more holistic sustainability of a local energy system such as the UVM
campus. A similar consideration is the sense of place the Gund holds within the larger UVM
context and its transition to a sustainable campus. Lani Ravin, a member of UVM Campus
Planning Services gave us the analogy that the Johnson House is like that of a fingernail on the
larger body of the university. With this in mind, we encourage the Gund to consider where
funding for solar panels might be most efficiently installed within the entire UVM campus.
There are many spots on campus that have been evaluated for panels, and while the Johnson
House is a somewhat feasible area, it is more efficient to put the panels on a more stable
structure. Installing panels on the roof of the Johnson House requires the roof’s stabilization and
renovation; such construction is costly, requires extraneous contractors, and is, ultimately,
subject to project termination should the installation conflict with the historical regulations of the
house. We conclude that if panels are placed on a more stable foundation (such as a parking lot),
less funding would be needed.
Comprehensive Plan Summary
One of the most informative documents we found on the placement of solar panels was
UVM’s own Comprehensive Campus Renewable Energy Feasibility Study
(http://www.uvm.edu/sustain/cef/cef-projects/comprehensive-campus-renewable-energyfeasibility-study). Not only does this plan go over the best locations on campus, but it also
provides relevant data on costs, permits, maintenance, and different styles of panels. If the Gund
is serious about getting zero carbon emissions by solar energy, pages 91-123 are going to be an
invaluable resource. More specifically, this study found several buildings and parking lots across
campus that could support PV panels. The Johnson House is one of these buildings. And the
predicted capacity for panels on the roof comparatively offsets more of the energy used inside
than many other buildings on campus. The Johnson House can support enough panels to produce
8.97 kW and this would reduce the building’s reliance on grid power by 38.78%, a relatively
high percentage compared to most other buildings. On top of this, the parking lot to the south of
the building, can support panels for 55 kW which, according to the plan, would offset only
35.5% of the building’s energy consumption.
Johnson House’s Electricity Usage (2011-2012)
Month
kWh
Month
kWh
October
2280
April
2280
November
2360
May
2240
December
2200
June
2320
January
2240
July
2680
February
2200
August
2320
March
2400
September
2240
Subtotal
27, 760
kBtu Total
87, 222
Figure 1. Energy audit data. Johnson House’s electricity usage for 2011-2012 - not including
natural gas usage.
Figure 2. “Energy Cost per Kilowatt Hour”
Figure 3. “102 24.5 kilowatt carport mounted solar panels”
Approximate Costs of Panel Types
Solar Panel Type
Approximate Cost Range (Not
including labor)
-Solar Photovoltaic Tracker (5640 kWh/year)
$8,000 - $12,000 per tracker
-Parking lot Solar Installation (24.5 kW system or
2000 kWh/year)
$1,500 - $2,500 per panel
-Rooftop PV System (5kW system or 5400
kWh/year)
$14,000 - $30,000 for total system
+ cost for roof stabilization
Figure 4. Comparison of Cost and Location for Solar Panels
Discussion of Other Solar at UVM
In 2010, the Aiken building at UVM invested in solar panels to power their building. All
Earth Renewables installed 17 of their Series-20 All Sun Trackers, which cost $200,000. These
are supposed to produce 71.4 kW of electricity per year, but have actually produced closer to
100,000 kWh per year. The Johnson house needs about 25,000 kWh per year, or about 4 of the
trackers, to produce enough to meet all of their current energy needs. This could need be
decreased through more efficient use of electricity. The panels at Aiken give us a useful idea of
how much solar energy we can expect to receive in this area.
Conclusion
We recommend the use of carport mounted PV solar panels in the parking lot adjacent to
the Johnson House; the panels could be south facing and seen from Main Street as a model of
renewable campus energy. Depending on the Gund Institute’s total project budget, the solar
panels’ energy production can replace a portion of the current electricity use or its entirety. We
strongly suggest using grid tied solar panels, due to its less wasteful and more efficient structure.
References
"Grid-Tied Solar Power Systems with Battery Back-up." Wholesale Solar. 2013. Web. 20 Apr.
2014. <http://www.wholesalesolar.com/grid-tie-battery-backup.html>.
"Incentives: General Information." Renewable Energy Resource Center. Vermont Energy
Investment. Web. 23 Apr. 2014. <http://www.rerc-vt.org/incentives-program/generalinformation>.
"Off-Grid Vs. Grid-Tied Solar." Revision Energy. Revision Energy, n.d. Web. 23 Apr. 2014.
<http://www.revisionenergy.com/off-grid-solar-vs-grid-tied-solar.php>.
"Solar - Grid-Tie or Off-Grid?" APRS. APRS, 2013. Web. 25 Apr. 2014.
<http://www.aprs.org/off-grid-maybe.html>.
"University of Vermont Solar Installation." All Earth Renewables.
Web. 26 Apr. 2014. <http://www.allearthrenewables.com/assets/Uploads/
Case-Studies/Case-Study-UVM-V9.pdf>
"Vermont Incentives and Policies for Renewables and Efficiency." Database of State Incentives
for Renewables and Efficiency. North Carolina State University, 2013. Web. 23 Apr. 2014.
<http://dsireusa.org/incentives/index.cfm?re=1&ee=1&spv=0&st=0&srp=1&state=VT>.
"Vermont Solar Consumer Guide: Solar Photovoltaic." Renewable Energy Vermont. Renewable
Energy Vermont, 2014. Web. 18 Apr. 2014. <http://www.revermont.org/main/gorenewable/photovoltaic/>.
Appendices
Work Log
April 7 Kendall begins email conversation with Lani
 Found electrical bill
 Research historical codes
 Outlined project
April 14 Progress update with Deane
 Ashley works at geospatial lab
 Kendall emails Lani to set up meeting time
 Manya writes draft for her research
 Oliver starts looking at tax exemptions or incentive sources
April 18 Meeting with Lani at 3:15pm
 Search through Sustainable Energy Audit (pieces given by Lani)
 Research guidelines in the Campus Planning notebooks
April 21 Progress update with Deane
 Read Renewable Energy Feasibility Study
 Started outlining final proposal
April 24 Complete draft of proposal submit to Deane
 Begin to finalize data to give to Gund
April 28 Hand-in final proposal (edits made based on Deane’s suggestions)
 Present to the Gund and HCOL 186