What do electricity bills look like with solar? My experience after two years

If you’re considering solar, it can be easy to imagine what solar panels would look like on your home: with nearly three million homes already installing solar around the country, you’re probably familiar with what solar panels look like on a roof. What can be harder to visualize is what your electricity bills will look like after going solar. Clearly, solar can save you money on your utility bills, but how does it actually work? 

With that in mind, here’s a look at what my National Grid bills looked like before solar, what they look like now that I’ve had solar for two years, and some bonus screenshots of how my usage has changed with additional energy upgrades. As an EnergySage employee, I’m obviously a solar advocate, and we certainly care about our environmental impact. But, we wouldn’t have gone solar unless it made financial sense, and it most certainly did: I haven’t paid an electric bill for my home in Massachusetts since September 2019, which is just as great as it sounds.

Electricity bill pre-solar

We put solar panels on our home two months after moving in. Since we knew we knew we’d be installing solar heading into the purchase of our home, we actually got a year’s worth of electricity bills from the previous owners of our house at closing to help us size the solar panel system we would need. But, we also had a couple of months of electricity bills pre-solar. Here’s what those bills looked like: 

2019 National Grid Bill

In our first full month in our house, we used 667 kilowatt-hours (kWh) of electricity (mostly running central AC), and our bill was $154.82. After subtracting the $5.50 customer charge, that meant we paid an electric rate of 22.4 cents/kWh ($149.32 / 667 kWh). 

That’s a lot to pay for electricity! According to the Energy Information Administration, the average cost of electricity for residential electricity users was 13.01 c/kWh in 2019, so our rate in Massachusetts was certainly on the high end. And it’s only getting more expensive: if I didn’t have solar today, I’d be paying a $7.00 monthly customer charge and 24.9 c/Kwh for electricity: an 11 percent increase in the rate in two short years.

While $150 a month may not sound like much, it adds up quickly over the course of the year, and over the lifetime of a solar panel system: without solar, we would have spent $58,000 over 25 years on electricity, and $73,000 over the next 30 years, assuming a $150 monthly bill, with a 2% annual increase in electricity rates. 

Needless to say, we were very excited to install solar and start saving money on our electricity bills! 

Electricity bill post-solar

In the 24 bills since we received our permission to operate in September 2019, we haven’t owed a dime on our electricity bills. In fact, because of the SMART incentive in Massachusetts, not only do we no longer pay $150 each month for electricity, now National Grid actually sends us money, normally between $60 and $90 per month. So we’re not just saving, we’re actively earning money each month. Quite the deal! 

Here’s what a typical bill with solar looks like for us: 

National Grid 2021 Bill

A couple of things to point out:

  • The most important number, for me, is the amount due: $0.00. Love that. 
  • This July, even running our AC all the time in the heat of the summer, we were still net exporters of energy, with negative total usage over the course of the billing period (we may have oversized our system slightly – oops). 
  • Because we produced more than we used from the grid, we received a net metering credit of $80, which means we had more than enough credits to cover the $7.00 customer charge and the distributed solar charge. 
  • And, since our overall bill was negative (again), we have quite a bank of bill credits–nearly $1,200 worth. There’s no additional value to this–National Grid won’t pay us out for those credits–but it does mean that we could increase our energy usage and comfortably have enough credits to continue not paying bills for some time. 

SMART incentive

In addition to not owing anything on our bill, the SMART incentive program actually paid us $63.74 this month: 

SMART incentive

The calculation of the SMART adder is a bit tricky, but it’s based on how much solar we produced in the month (729 kWh), the value of energy when we installed solar (19.9 c/kWh) and the SMART rate when we registered (28.7 c/kWh). In months when we produce more solar (like the summer), the monthly payment can approach $100. In months where we produce less (like the winter), it can drop to $40 or so. But over the course of the year, we receive over $800 in incentive payments. FYI: it’s taxable.

Bonus: a look at consumption pre- and post-ASHPs

Despite not spending anything on electricity in two years, we still had natural gas bills for heating in the winter months, often exceeding $250 a month in the coldest part of the winter. So, with all of that extra production from our solar panels, and all of those extra credits on our bill, we decided to swap out our old gas furnace and old AC unit for high efficiency, electric air source heat pumps (ASHPs) with a backup gas generator for the coldest days of the year. Here’s how our production and consumption compares on the hottest days of the year when we’re running the AC at full tilt. 

Our old central AC condenser used to draw a full 4 kilowatts of power when it was on. Looking at the screenshot of our solar app on the left below, each bar indicates kWh of production or consumption over a fifteen-minute period. So 1 kWh of consumption means 4 kW of power pulled for 15 full minutes (4 kW * 0.25 hour = 1 kWh). On a day like July 27, 2020, our solar panels produced 38 kWh of electricity, but we consumed 36 kWh of electricity cooling the house – so nearly even.

Pre- and post-ASHP usage

After installing electric ASHPs, however, our AC power demand is actually lower, as shown on the screenshot of our solar app on the right above. At peak, our AC only uses 2 kW and often runs at less than 100 percent capacity with a variable drive motor, unlike our old AC unit which was either 100 percent on or 100 percent off. As a result, even on days when our solar production curve isn’t perfect (get out of here clouds!), we’re still able to keep our home nice and cool and come nowhere close to using all of our solar generation. 

Sign up for an account here, and don’t hesitate to tell us about your solar experience!