8.04 kW high-efficiency SunPower solar system – Ipswich, MA
“Today is our third severe storm in less than two weeks. The first storm hit Ipswich pretty hard; it caused astronomical tides and flooding. We were out of town, but our area lost power. Because of our battery backup, our home was able to keep warm and functioning. Our neighbor came over to store food in our fridge and charge her phone. The second storm caused a power outage lasting a couple of days. This was a chance for us to test our battery system.”
The Kahns have a SunPower solar system with battery backup that was installed by IPS in 2014. Their 8.04 kW system takes care of about two-thirds of their electrical usage, part of which is “fueling” their plug-in hybrid electric car. When the grid goes down, the solar system keeps functioning by charging the battery system and powering house loads.
“Our system has eight batteries which allows for 17 hours of critical load use. When the grid goes down, the system switches over seamlessly to the batteries. Our critical load is the sump pump, heat pump, furnace, range, fridge, some lights. Ours is an almost all-electric house. We heat mostly with a heat pump and a modern woodstove fire place insert that generates a lot of heat. When the power recently went down, we went to wood heat and did basic cooking on our wood stove fireplace insert. Many people’s houses got very cold and people had to move in to shelters. But we were toasty and comfortable with our wood fire. We know to be conservative in our use of electricity, but it was good to know that we had plenty of hours of use. When the electricity came back on, the batteries charged right back up from the grid. 2015 was also a very difficult winter – lots of snow. We were worried about how our system would be affected by the snow, but there were no problems. It’s a good feeling to know you can be self-reliant.”
What motivated you to consider a solar electric or PV system for your home?
We cared about climate change and felt it was our responsibility to use clean energy.
What allowed you to move forward on deciding to invest in a PV system?
We had an assessment of our roof orientation. We got a referral to IPS, met with a technician, went over the specifics and decided to go for it. Of course, we were pleased to be able to take advantage of the local, state, and federal incentives.
Has your system worked as you expected it to?
Yes, it has exceeded our expectations. Especially with the batteries. At first, I didn’t realize how capable our system was. I’m kind of surprised. We thought we’d have to wait for Elon Musk to come up with something. Our system, now three and a half years old, is perfectly sufficient.
Your system has a battery backup component. In your words, could you explain how it works and what has it done for you?
There’s nothing much to do; it just works. That’s what we’ve learned.
If you had to put a value on never losing electrical power, what would that be?
The value is peace of mind, not a monetary value. In a real emergency, we can be self-reliant and help others in our town.
Do you feel you have or will get your ‘money’s worth’ from the battery backup system?
Are you happy with IPS’s performance in working with you and delivering as you expected?
Yes. It has been easy to get answers to questions; everyone has been very responsive and helpful. We were referred to IPS by friends, and we’ve referred other friends.
What would you like to say to someone considering going solar?
It’s kind of a revelation that you really can turn your house into a generator of clean energy – so long as your house has the right orientation and you can afford it. You really do feel that you’re part of the solution. I think it’s one of the best investments one can do insofar as addressing climate change and building a resilient house and community.
Panels:  high-efficiency SunPower 335 – 8.04 kW system
Estimated Annual Production: 9,500 kWh
Inverters: Power One 4200
Batteries: 8 Trojan AGM
Interested in learning about battery backup for your home? Chat with a friendly solar technician at Independent Power Systems.