Author By :Neil Froemming
Wed, Mar 21, 2018 2:14 pm
We have a new solar array at our Quaker meetinghouse near Dupont Circle.
We just got our electric bill for Feb-Mar — the first month of solar panel usage.
Perhaps it will help you to understand Pepco billing to see the before and after record for our March bills.
If you look at the comparison below, you see that in our bill for March 2016, we used 6589 KWh and paid about 11.4 cents for each kWh. Almost the entire bill was based on charges for the energy we used.
In June of 2016, Pepco came and changed our meter to a “smart meter” that could track our usage. Then, they changed us from a residential rate to a non-residential rate. You can see that our March 2017 bill was higher, even though we used less power. That’s because the rate went up a bit, but mostly because there’s a new “Maximum Demand Charge” that is not based on usage, but on how fast we used energy during a particular peak period. So $186.57 of the bill would not be affected by our solar panels.
When you look at the March 2018 bill, you see that we used less power from Pepco, because our new solar panels generated some power. But the Maximum Demand rate had increased, so now $328.29 of the bill is not based on usage.
Pepco can’t see the power our panels generate (unless they generate more than we use). They just see the difference between what we use and what we produce, which is the amount we draw from them (or give to them).
You can see below those Pepco numbers that our solar panel production metering reported that the panels produced 1,738 KWh during the billing period. We can add that to the 3,760 KWh that Pepco says they sold us and find our total usage — 5,498 KWh. That’s close enough to the prior year to be plausible.
2016 2017 2018
Billed Usage (KWh) 6589 5200 3760
Rate – cents per KWh 11.4 12.3 11.5
Usage Charge 753.92 638.58 430.86
Customer Charge 23.39 27.11 31.07
Maximum Demand Charge 159.46 297.22
Total $ 777.31 825.15 759.15
Solar Production (KWh) 1738
Total Usage 6589 5200 5498
Solar Production($) 199.16
We can multiply the 1,738 of production by the billing rate that Pepco charged us in March and calculate that we saved about $199 on our March Pepco bill.
Someday, we imagine, we will get SRECs for the reported generation, and will have saved another $700 or so.
If you ask how you can check to see whether Pepco is telling the truth about your usage and production on your electric bill, the short answer is — You can’t, unless you buy your own electric meter and stick it next to the Pepco meter.
But that’s nothing new. Before you got solar panels, you had to trust that Pepco meters were accurate. That hasn’t changed.
What has changed is that Pepco (Exelon) is proposing to charge mximum demand charge to residential customers. I see that some folks are very upset about that, but solar panel owner’s in DC are getting such a ridiculously good deal on SREC’s that I find it hard to be outraged. We stand to pay for our panels in 5 years and then continue to make a very large profit.
And we do continue to expect Pepco to stand by to provide us electricity on cold January mornings, when our demand is highest and our solar production is neglible.
In our case, our Meeting is being billed on a nonrsidential-demand tariff, and they calculate the “maximum demand” as the highest ½-hour demand during the month. That doesn’t make a lot of sense, in terms of energy policy. They should be calculating our demand during Pepco’s highest demand period, because that’s what drives their need for stand-by capacity. Our biggest peaks aren’t even in the summer.
Better yet, they should just charge us more for power we use during Pepco peak periods. Then we help find ways to improve the situation.
I would urge Solar United Neighbors not to just protest against maximum demand charges, but to protest in favor of a sensible alternative.