There isn't any guesswork in how your utility normally bills you for energy. There shouldn't be any guesswork involved in knowing your savings on that bill thanks to your solar energy installation. Follow these easy steps to track your monthly savings using just two numbers: the billable kWh on your utility statement and your total consumption kWh from your home energy monitoring app.
Understanding the fundamentals
When we talk about savings from going solar with a net metering program, we have to do a little exercise with our imagination: picture your home without solar. This helps when you look at your utility bill with solar, which only show the net energy during that month that you are being charged for. If you know about how net energy metering works, it's easy to get bogged down in questions like:
- Does this bill reflect the times when I sent energy to the grid during the day?
- What's the value of the solar power I consumed?
- How did differences in conditions (milder or more extreme weather for the season for example) influence this bill being higher or lower than last year?
That's why when you're going about estimating your solar savings, it's important to try not to get wrapped up in extraneous detail and just focus on isolating one thing: What you would have paid for all the energy you used during this 30-day period if you hadn't gone solar, versus what you actually paid to the utility.
The easy math of solar savings
This example is going to be for Dominion Energy residential service customers in Virginia, but the principle is the same other places - that's just the territory we have the greatest number of customers in right now.
Start with this interactive worksheet. Start by choosing the season and filling in the ending month of this bill cycle. Then, drop in the billable usage kwh number from your utility bill. Voila - the total bill cell at the bottom of the worksheet should be the same as the bill the utility sent you.
So that's your low bill with solar. How high would your bill have been without solar? If you have the Enphase Enlighten app, it's easy to retrieve that kwh usage number for how much you used. This is different than your utility billable kwh because that number is already netted, in other words its less the amount of your own solar power you used and accounts for account credit you used at night that you had accrued at times when you had excess solar energy.
In the Enphase Enlighten app, go to Menu - Reports. Select "Daily Consumption" and then set the dates for your request to correspond to the dates for your recent utility billing period. Once you submit this request, you'll receive a chart in your email that will provide your daily and total consumption for those 30 days. The total will probably be in the thousands of kWh. (Do the numbers look big to you? Check the units in the chart heading - it's probably in Watts rather than kilowatts and should be divided by 1,000.)
There's the number you can plug into the same cell in the Dominion customer bill worksheet to estimate how big your bill would have been without solar. Subtract your actual bill from the sans-solar bill and presto, there's your savings!
Unable to use the Excel worksheet? Contact email@example.com and someone on our consultation or marketing team will run the worksheet for you. We don't need you getting confused with distribution rates, generation rates, and transmission rates - which are all built into this worksheet.
At any scale: Larger homes and more solar panels
In the example below, the customer expected to save about $100 a month from solar, give or take, depending on sunny versus overcast days and the time of year. By crunching the numbers, she can see that yes, she has saved over $90 in this 30-day period from what her bill would have been, by producing about 800kWh of solar power that she was able to use an avoid paying the electric utility for. This home has about a 6-kiloWatt solar installation made up of 19 panels.
A larger solar installation is going to be responsible for greater estimated savings, and the proof is in this simple math, assisted by the utility. Some systems more than 10kW in size in Virginia may be subject to monthly fees - take care to make of these in your bill if they apply to you and factor this in, to keep from making mistaking with discrepancies in your arithmetic. Also, if you can't explain numbers being off, check for local taxes as an item on your utility bill, or conversely, pay attention to credits like the base rate case credit which now appears on utility bills and may be changing your total - this item applies in your with solar and without solar scenarios.
Every solar customer knows at least one solar skeptic - maybe they're a neighbor, a coworker, or a member of your own family! Next time they're asking if solar is saving you money, they don't have to take your word for it! If they're game to take a look at the figures, they'll see the savings are real. Plus, the solar energy system you own won't be raising rates on you, and the price of the sunshine that you rely on won't be going up, so the benefits from your shrunken utility bill will only grow!
Don't have solar yet, or have a friend who needs a quote? Get in touch today!