My husband Dan and I feel very fortunate to live in the “Green” Mountain State of Vermont. In recent years, programs have emerged that have brought clean, renewable and affordable energy to the residential sector in the form of solar PV plus battery storage.
Our path to solar plus storage has been a two-stage process, beginning in 2017 with our decision to go solar. That summer we heard about a presentation to be given at a local restaurant by a Vermont solar installation company, SunCommon. We have long-been environmentally conscious, being avid recyclers and owning a hybrid vehicle, so our interest in solar was piqued. What we heard at the presentation convinced us of the financial benefits of installing solar panels through net metering with our electric utility, Green Mountain Power (GMP). At the time, the federal tax credit available was 30 percent; the panels could be purchased up front, with a cash discount, or financed with our local credit union, VSECU, for 12 years at a low interest rate. With the financing option, the tax credit received would be used to pay down the loan. We walked out of the presentation excited about the upcoming site visit that we had scheduled.
The site visit involved taking a deeper dive into cost savings, by taking into account our annual outlay for electricity and the payback period for the cost of the panels. We were also given estimates of the number of panels necessary to power our home under various options, including the addition of air source heat pumps. In the end, we opted to have 27 PV panels installed in a rooftop mount, adding a few extra panels for a heat pump to supply heating and cooling to an area of our house heated with propane. The net cost, after the cash discount, design rebate and the 30 percent federal tax credit was $21,150. Our annual outlay for electricity at the time was $1,600. After two full calendar years of solar power, we are saving about $1,400 annually in electricity costs, and we have not exhausted the solar credits in our net metering bank. Given this, the payback period for the net cost of the panels will be about 15 years. Solar panels will generate at maximum energy production for a period of 25 to 30 years, after which production will decline significantly. This will result in an additional cost savings of between $14,000 to $21,000 dollars over the lifetime of the system. Our investment will more than pay for itself with the added benefit of increased re-sale value of our home.
Two years after our solar panel installation, SunCommon contacted us to let us know about the Resilient Home program being rolled out by GMP. GMP was offering its customers a great deal on two Tesla Powerwall batteries. Buying into the program would allow our PV panels to work in tandem with the batteries, providing electricity to our house when the power grid was down. A double Powerwall system retailed for about $22,000; GMP would lease the system for either $30 per month for ten years, or one up-front payment of $3,000. Installation would be free as our house had the 200-amp service necessary to the system, and any warranty issues and maintenance would be the responsibility of GMP as owner of the batteries. An integral part of the program was sharing the stored energy with GMP, allowing them access the batteries during peak power events – which will also help to bring down electricity costs for other GMP ratepayers. Any energy used by GMP would be deposited back in our net metering bank at a higher rate. Living in a rural area with many trees around the power lines, where power outages are not uncommon, this offer was too good to pass up.
Our Powerwalls were installed in January of 2020. To date we have experienced one brief outage. Our batteries kicked in immediately with no interruption of service and no need to reset clocks or timers. In the event of an extended outage, our Powerwalls will provide electricity for 16 to 24 hours; longer with careful energy use and sunshine to allow our panels to concurrently charge the batteries. When a weather event is forecast, GMP takes care of customers by ensuring the batteries are fully charged and ready to go.
Dan and I feel so fortunate to have been able to take advantage of these clean energy programs, but more importantly to live in a state that is committed to renewable energy. Here, solar installation companies, utilities and financial institutions partner to bring resilient power to Vermont’s residents, so that together we can all benefit.
Editors note: GMP’s Powerwall offer is currently full but reopens in January 2021. Enroll now at http://bit.ly/GMP-PowerwallOffer to get on the waiting list.
This article was originally published in Green Energy Times.