My Experience with a Rooftop Solar System
I’ve volunteered to be on the route of my community’s Fall Eco-tour, which means that (hopefully) neighbors will visit my home to learn more about how I’m working towards improved sustainability. I thought it might be helpful to have a page that gave some practical details about my own experience with installing solar panels.
I will address:
Installation, size and cost of my system,
How much electricity it generates,
Info about my utility’s Distributed Energy Program. I’ve included links to articles about bills currently being considered by Michigan legislators that will improve terms for rooftop and community solar projects.
My savings
Installation, Size, Cost of System
Based on recommendations and price, I went with The Green Panel based in Brighton, Michigan. They conducted a site visit to understand where to site the array. As a suburbanite, my only choice was to mount the panels on the roof. If you have room to site the array on the ground, that may be better because you don’t have to worry about the added expense of dealing with the panels if you need roof repairs. I handled this by getting a metal roof a few years earlier than I got the panels. Typically a metal roof is going to outlive the panels.
It’s likely that Green Panel also assessed the condition of my roof to understand if it could handle the load of a solar system. For more information about how to think about load and if your roof can handle it, look at the Energy Sage website Solar panel size and weight explained: how big are solar panels?
Next, the company asked me for my electric bills so they could understand our energy use. For comparison’s purposes, it might help to know that I live in a 3-bedroom, 2000 SF ranch.
Green Panel recommended a 5.58kw system, which comes out to be 18 panels, each approximately 40” x 66”. The specific panels are made by Mission Solar, MSE PERC 60 and come with a 25 year warranty.
Installation: The company handled the permits. If I remember correctly, the complete installation took one day.
The cost for materials and labor was $14,500. I paid for it by refinancing my mortgage. I also got a tax rebate of 30%, which means my final cost was $9,650.
The Inflation Reduction Act will provide credits and rebates for residential solar installation, but implementation has been slow. Before you assume that you will get the credit, check with a tax professional.
My rooftop solar panel arrayElectricity Generation
Part of my reason for doing this post is to make rooftop solar seem like a normal, easy-to-understand, and easy-to-transition-to thing. Cost is part of that, but people have other reservations about this pretty big decision, which may have to do with uncertainty about energy reliability or the technology itself.
Below are some screenshots that I can use to look at how much my panels are generating at any given time. I think they make it easy and fun to track.
This is what I see when I open the SolarEdge app on my phone.
Annotated screenshot of the SolarEdge app, which is on my phone and tells me in real time how much solar energy I'm capturing.Current energy production by day, week, month, and year. I can look at this and know at this moment, what I've produced for one of those time periods.These screens let you compare your production over a period of years. You can compare how much production you get by month, by quarter, and by year. I got my panels on September 11, 2019.The Distributed Generation Program
My system is tied into the electrical grid. My utility company, Consumer’s Energy, runs a Distributed Generation program. This means that the power I generate goes back into the grid, and I’m actually accessing my electricity in the same way that all of my neighbors are. Consumer’s Energy subtracts what I produce from my overall electricity costs each billing cycle.
Ideally, one day I’ll have a battery back-up system, which will give me more control. I want a battery because:
Sending electricity back to the grid is inefficient. My understanding is that, at best, you lose 20% of what you produce when it is sent back into the grid.
Consumer’s Energy pays Distributed Generation customers less for the electricity they generate than what they charge. John Richter from Great Lakes Renewable Energy Association says:
“When a Michigan utility buys energy from a customer with solar, the utility pays a much lower rate than it charges the customer for the energy they buy from the utility (at night, for example),” he said. “The utility then sells that energy, usually to their next-door neighbor, at the full rate – a 100% markup! This bill would establish a fair-value tariff for the sale of energy to the utility and end the legal limitation on how many customers may do so.” (source: Planet Detroit).
Extreme weather makes it more likely the power outages will occur. I’d love to have a battery to provide electricity in those situations.
I have not recently looked into the cost of batteries, but I understand the cost has gone down since 2019. It might be worth looking into that possibility if you decide to get a rooftop system.
Before diving into the savings, I want to say that my reasons for getting solar panels had less to do with the ‘payback’ and more to do with the idea that we should all do what we can to transition to a more sustainable way of living. Even so, it’s annoying that the terms of the Distributed Generation program are so heavily in favor of the utility.
There are several bills being considered by Michigan legislators that would improve the terms for residential power generation. You can learn more at this post from Michigan Advance. I agree with Jeff Irwin (D-Ann Arbor) when he says:
“We have to have a free, fair and functional system and the law must allow people to plug in and contribute to our clean energy future…So to ensure that we meet these ambitious climate goals, we absolutely need to lift the cap on distributive generation.”
How much am I saving?
I took a screenshot of my bill for the periods of January 1-February 4, and of July 5-August 2. SolarEdge keeps track by month, so doesn’t match up exactly with Consumer’s Energy billing period, but I thought it would be close enough to show you how the Distributed Generation program works. You can see that I’m only getting paid for a fraction of what I generate, and I’m also getting paid less than fair market value.
Comparison of my January electric bill with SolarEdge data.Comparison of my July electric bill with SolarEdge data.For the second example, SolarEdge tells me I generated 777kWh during July, but Consumer’s Energy is only crediting me with 329.082kWh. They tell me I used 470 kWh, so that means I still owe $9.84. If I accounted for the 20% reduction in efficiency, that would still be 621.6 kWh (777 x .2=621.6), which means that I should be banking kWh!!
For the purposes of this post and to answer the question, “how much I’m saving,” I looked at my electricity bills for the last 10 months. This table also shows how much energy I’m generating versus how much I’m being credited for by the power company. It’s the first time I’ve done an analysis like this, and, to me, it confirms that the power company is getting a much better deal. With that said, I’ll be writing to my representatives to urge them to pass the bills I linked to earlier in this post!
