There is a lot of information on the two or three pages that make up electricity bills in Rhode Island.   It is important to understand what you are paying for and what effect installing solar will have.  Below you will find information on how your electricity bill is structured and how a solar array is sized to produce the most value.

There are three main sections in a bill.  The “Delivery Service”, “Supply Service”, and “Other Charges/Adjustements” are added together to produce your total bill amount.

The delivery service contains a fixed charge and a charge based on a kWh electricity consumption; the per kWh cost will fluctuate with your kWh use and will be eliminated if you produce all of your own electricity.  These per kWh electricity delivery charges are actually wrapped up in the $0.17 per kWh that RI customers pay; National Grid just breaks it down into delivery service and supply service.

The first two line items under the delivery service part of the bill are fixed costs:

  • a $5.00 customer charge (for being connected to the grid)
  • a $0.73 LIHEAP charge (Low Income Home Energy Assistance Program)

Together at $5.73 per month, the total fixed cost is $68.76 per year.  Though these charges are fixed costs, National Grid accounts for solar production credit on your electricity bills on a dollar basis, not on a kWh basis.  This means you can pay for the fixed costs with overproduction.

Example 1:

You consume 300 kWh in March ($51.00 at $0.17 per kWh)

You produce 300 kWh of Solar Electricity in March

You receive a bill that month for $5.73

Example 2:

You consume 300 kWh in March ($51.00 at $0.17 per kWh)

You produce 334 kWh in March ($56.78 at $0.17 per kWh)

You receive a bill that month for $0.00


So, why is this important?  Typically when we size a solar array, we try to size it for a $0.00 electricity bills throughout the year.  Meaning, if a roof has space to produce more than all of the home’s electricity, we size to a point where the array produces at least $68.76 more than what the yearly kWh consumption would be.


The sales and installation process was straightforward, well communicated, and executed on time.