Rex says
Money math without the spreadsheet headache. Plug in your numbers and I'll show you exactly where the dollars land.
Try a scenario
Click to load — tweak from there.Inputs
Result
Total estimated monthly bill
$157.80
Generation/supply charge
$81.00
Delivery/transmission charge
$54.00
Riders and fees
$10.80
Effective blended rate per kWh
0.175
Share of bill that scales with usage
92%
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One click, a permanent link with your numbers baked in.
How to use this
- 1Enter monthly usage (kWh).
- 2Enter fixed monthly customer charge ($).
- 3Enter generation/supply rate ($/kWh).
- 4Enter delivery/transmission rate ($/kWh).
- 5Enter riders/fees as % of energy charge (%).
- 6Read your total estimated monthly bill on the right — it updates as you type.
- 7Hit Share to keep the scenario or send it to someone.
About this calculator
Most electric bills bundle several charge types into one number: generation/supply (the actual energy), transmission and distribution (delivering it to your house), and fixed customer/connection charges, plus in many states additional riders for infrastructure or renewable programs. This calculator breaks your total bill into those buckets using your utility's rate components so you can see what portion is actually reducible by cutting usage (mostly the volumetric generation and delivery charges) versus what you pay regardless of usage (the fixed customer charge) — a distinction that matters a lot when evaluating whether solar, efficiency upgrades, or usage reduction will meaningfully move your bill.
Worked example
Using the values the calculator loads with:
Inputs
- Monthly usage: 900 kWh
- Fixed monthly customer charge: 12 $
- Generation/supply rate: 0.09 $/kWh
- Delivery/transmission rate: 0.06 $/kWh
- Riders/fees as % of energy charge: 8 %
Results
- Total estimated monthly bill: $157.80
- Generation/supply charge: $81.00
- Delivery/transmission charge: $54.00
- Riders and fees: $10.80
- Effective blended rate per kWh: 0.175
- Share of bill that scales with usage: 92%
What each field means
Inputs
- Monthly usage (kWh)
- The monthly usage used in the calculation, measured in kWh. Starts at 900 kWh so you have a working example on load.
- Fixed monthly customer charge ($)
- The fixed monthly customer charge used in the calculation, measured in $. Starts at 12 $ so you have a working example on load.
- Generation/supply rate ($/kWh)
- The generation/supply rate used in the calculation, measured in $/kWh. Starts at 0.09 $/kWh so you have a working example on load. Accepted range: 0.01–0.4 $/kWh.
- Delivery/transmission rate ($/kWh)
- The delivery/transmission rate used in the calculation, measured in $/kWh. Starts at 0.06 $/kWh so you have a working example on load. Accepted range: 0.01–0.3 $/kWh.
- Riders/fees as % of energy charge (%)
- The riders/fees as % of energy charge used in the calculation, measured in %. Starts at 8 % so you have a working example on load. Accepted range: 0–40 %.
Results
- Total estimated monthly bill
- Returned as a money amount in US dollars and shown as the headline result. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Generation/supply charge
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Delivery/transmission charge
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Riders and fees
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Effective blended rate per kWh
- Returned as a decimal number. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Share of bill that scales with usage
- Returned as a percentage. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
FAQ
Why does my bill show a rate that doesn't match this calculator?
Many utilities publish a single blended per-kWh rate that already bundles generation, delivery, and riders together for simplicity, hiding the components. Your actual rate schedule or tariff (usually a PDF on the utility's website) breaks these out — use those specific numbers here instead of the summary rate for an accurate split.
Can solar eliminate my whole bill?
No — the fixed customer charge and, in many states, a minimum bill or grid-access fee apply regardless of how much solar you produce, since you're still connected to and using the grid for backup and any excess/deficit exchange. Realistically, solar offsets the volumetric energy charges, not the fixed connection cost.
What are 'riders' on a bill?
Riders are separate line-item charges layered on top of base rates for specific cost recovery — fuel cost adjustments, storm recovery bonds, energy efficiency program funding, or renewable portfolio compliance costs. They vary a lot by state and utility and can add 5-15% to a bill, sometimes more during periods of high fuel costs.
Is a higher delivery rate or generation rate worse for solar economics?
Delivery charges usually aren't avoided by net metering credits in many tariff structures — you might get full retail credit for generation charges but a reduced or zero credit for the delivery portion of exported kWh, which is part of why the net-metering vs buyback rate structure matters so much to actual solar savings.
Accuracy and limitations
- Results are estimates before tax, fees, and inflation unless an input explicitly covers them.
- Rates are treated as fixed for the whole period — variable-rate products will drift from this projection.
- This is educational maths, not financial advice. Check anything contractual with the lender or your accountant.
Related tools
Cite this calculator
Writing about this topic? Grab a citation — every link helps keep these tools free.
RevenueLab. (2026). kWh Electric Bill Breakdown Calculator. Retrieved from https://www.revenuelab.fyi/toolbox/kwh-bill-breakdown
<p>Source: <a href="https://www.revenuelab.fyi/toolbox/kwh-bill-breakdown" target="_blank" rel="noopener">kWh Electric Bill Breakdown Calculator — RevenueLab</a> (2026).</p>
Source: [kWh Electric Bill Breakdown Calculator — RevenueLab](https://www.revenuelab.fyi/toolbox/kwh-bill-breakdown) (2026).