When clients relocating from Colorado told me they were installing a solar system in their St. Paul home I asked if they would be willing to share their experience. They said yes! Here is their story.
Solar in Saint Paul
We had solar power in Colorado from 2008 to March 2020 when we moved to an urban neighborhood in Saint Paul. For those 12 years, our system more than offset our electrical consumption; and we wanted the same benefits at our 1968 vintage, single-story house in Minnesota. This blog describes the situational physical challenges we experienced, and the equipment technology improvements that occurred since the 2008 Colorado system installation. The entire process from start to commissioning in Minnesota took from mid-April to mid-September 2020. Xcel Energy is the utility company we had in Colorado and now have in Minnesota, but there are differences in the state programs.
Because we are new owners of the property and do not have a history of energy use here, the system’s size was capped at 120% of Xcel’s anticipated consumption for our house. We wanted to produce the most solar power we could, so our system was designed at the maximum allowable size, 4.68 kW. This calculates to expected production of between 4-4.5 kWh given the site variables that affect the solar resource (e.g., shade, aspect, clouds), but we should meet, and maybe exceed, our consumption. Our Colorado house was very solar-friendly in terms of aspect and more sun, but it was more than twice as large as our Saint Paul place, and we always produced surplus electricity there.
The Saint Paul house presented these new-to-us power-production challenges:
- the orientation is not optimal — there are two simple roof sections that slope east and west away from the north-south centerline
- the lot is narrow – 40-feet wide, with shadows cast from deciduous trees and two-story neighbor houses on both east and west sides
- squirrels are prolific and climb from the trees to the roof – possibly causing wire-chewing damage to the arrays
- the roof slopes are not steep, so snow may not easily slide off the panels during portions of the winter
- the roof shingles were new in 2018, but the 52-year-old attic roofline showed some deflection which concerned us from a structural perspective
We used All Energy Solar in MN to help us address these challenges through:
- a series of phone calls for a thorough discussion of the likely options and financial considerations
- a site assessment from a designer that included evaluation of our roof and attic structures
- development of a custom design that fit the contours of our sun/shade profile and included a “critter guard’ to prevent squirrel wire-chewing,
- obtaining city permits from Electrical and Building Departments
- signing a net metering and Solar Rewards contract, and an interconnection agreement with Xcel
- connecting with Xcel systems using new meters
- installation (2 days span) that occurred safely even amidst a neighbor’s emergency large, damaged tree removal
- and establishing production tracking through software.
Although both our Colorado and Minnesota systems were sized nearly the same (4.725 and 4.68 kW respectively), the differences were:
- innovations in panel capacity (2008-vintage panels rated at 225 watts per panel – the 2020 panels produce 390 watts per panel), allowed for a reduction in the number of panels from 21 to 12.
- the new panels are also lighter, and each has its own microinverter (converts sunlight — Direct Current, into Alternating Current used on grid) which eliminates the need and cost for a single, large inverter. This made panel configuration optimization easier: 9 panels on the west roof, 3 panels on the east roof, and we were able to dodge the roof vents on both sides. Because our attic has a knee wall and the panels are lightweight, our concern about the roof deflection was eliminated.
Monitoring and Metering
Xcel systems in Minnesota require two meters instead of the single net meter we had in Colorado. In Minnesota, Xcel replaced our standard consumption meter with a bi-directional meter which tracks net power usage by spinning forward when we use electricity from the grid, and backwards when our system creates more power than we are using. Xcel also added a new meter which tracks only production from our solar system (a monthly metering charge is paid to Xcel). There is also an emergency shut-off for the panels to protect Xcel workers repairing the grid following outages, and a control box for the energy system tracking software provided by Enphase (accessible online and with cell phones).
An example first full-month report from our monitoring software is shown below:
Under the Xcel Solar Rewards program in 2020, the homeowner receives a fixed production payment (7 cents per kWh, the 2020 wholesale rate) recorded by the solar energy production meter and paid out annually for 10 years. For our system, we expect to receive a Solar Rewards check for about $328 each year during the ten-year period.
We will also get a monthly check when our system produces more electricity than we use, which is paid at the retail rate for electricity. The 2020 retail rate for electricity from Xcel is 13 cents per kWh and is expected to rise by 3% per year.
In addition to the Solar Rewards payment and the monthly surplus energy payment, solar customers in 2020 are also eligible for a federal tax credit of 26% of the total system cost (note: this is reduced after 2020 ends). Our system cost $14,746, so we can take a $3844 credit on our 2020 taxes. For us the total incentives brought the system costs down to a reasonable amount, with an expected payback of about 7 years. We also anticipate little or no monthy electricity payments for the life of the system.
One thing that we didn’t expect is that a Minnesota law requires homeowners with grid-tied solar to have a minimum of $300,000 in personal liability insurance coverage. This is typical for most homeowners and was not an added expense for us.
Additional paybacks may come in the form of increased home value and reduction in market time when we sell. A 2019 analysis by Zillow determined that on average, solar panels raise a home’s value by 4.1% across the US. Based on that study, the boost in home values from solar was $12,300 on a $300,000 home. And the Department of Energy, National Renewable Energy Laboratory estimates that a solar electric home would sell 20% faster than one without the system.
Based on our 12-years of solar system ownership in Colorado, we expect there will be little maintenance needed, although we have not had the panels for a full year of Minnesota seasons yet. In Colorado, our panels were not damaged during three major hailstorms that required re-roofing (the cost to have our solar company remove and replace the panels was covered by our home insurance).
We expect our system to have a life-expectancy of 30-40 years, and there are warranties for the panels and microinverters for 25 years with an installation warranty that lasts for 5 years. For us, the decision to have solar panels makes sense on many levels, especially since we intend this to be our retirement home.