Everyday Calculators
Electricity Usage Break-Even Calculator
Compare confirmed net project cost with entered annual kWh savings, current avoided rate, annual rate change, maintenance, useful horizon, and cumulative net value.
Net project cost after confirmed rebate-
First-year avoided electricity cost-
First-year saving after maintenance-
Simple first-year payback-
Gross avoided electricity cost through horizon-
Maintenance through horizon-
Net benefit through horizon-
Net horizon return on project cost-
Decision view
Cumulative electricity-project value
Cumulative electricity-project valueEscalating avoided electricity cost and annual maintenance build a year-by-year net-value path from project outlay to break-even.
Exact scenario comparisonEstimated electricity saving per year (kWh) changes while all other entered assumptions remain constant.
| Estimated electricity saving per year (kWh) | Net project cost after confirmed rebate | First-year avoided electricity cost | First-year saving after maintenance | Simple first-year payback | Gross avoided electricity cost through horizon | Maintenance through horizon | Net benefit through horizon | Net horizon return on project cost |
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How to use Electricity Usage Break-Even Calculator
- Use an engineering or measured annual kWh saving.
- Enter only the avoidable variable rate.
- Stress-test rate change, maintenance, degradation, and useful life.
Calculator guide
Understanding Electricity Usage Break-Even Calculator
An electricity-saving project should recover its net cost from avoided energy charges after maintenance, with rate escalation kept distinct from simple first-year payback.
Detailed calculation process
Test project recovery from avoided electricity cost
The default subtracts a confirmed $1,200 rebate from a $5,500 project, values 4,200 annual saved kWh at $0.22, deducts $75 annual maintenance, and projects twelve years at 3% annual rate change.
General formula: K_n = max(K-R,0); G_1 = E_s r; N_1 = G_1-M; P = K_n/N_1; G_h = G_1 sum(j=0..y-1)(1+g)^j; H_n = G_h-My-K_n Simple payback uses first-year net savings. The horizon model separately compounds the avoidable rate while annual kWh savings and maintenance remain constant.
What each symbol means
Worked substitution with the default inputs
The default project has a $4,300 net cost and $849 first-year net saving, producing about 5.06 years of simple payback before the separate twelve-year escalation model is considered.
Project audit
Make every cash-flow driver defensible
A reliable break-even result should trace to evidence.
Worked situations
Practical examples
- 4,200 kWh at $0.22 avoids $924 in the first year.
- $75 maintenance reduces first-year net saving to $849.
- Rate escalation affects cumulative horizon savings but not simple first-year payback.
Better inputs
Useful tips
- Use zero escalation as a conservative scenario.
- Exclude fixed charges that remain on the bill.
- Compare payback with warranty and replacement timing.
Before relying on the result
Limitations and common mistakes
- Taxes, financing, depreciation, degradation, replacement, demand savings, exports, and discounting are excluded.
- Annual kWh saving remains constant.
- The entered rebate is treated as confirmed.
Reference
Key terms
- Avoided rate
- Variable price not paid for each saved kWh.
- First-year net saving
- Avoided energy cost less annual maintenance.
- Simple payback
- Net project cost divided by first-year net saving.
- Return on cost
- Horizon net benefit divided by net project cost.
Important note
Measurement references: U.S. Department of Energy, Energy Saver (https://www.energy.gov/energysaver/energy-saver) and Efficiency Valuation Organization, IPMVP (https://evo-world.org/en/products-services-mainmenu-en/protocols/ipmvp). Verify savings, incentives, and tariff treatment with project records.
Frequently asked questions
Why exclude the fixed service fee?
It usually remains after the project and is not avoided.
What if first-year net saving is zero?
There is no finite simple payback.
Does the horizon model include present value?
No. It is a nominal cash model.
Can demand savings be added?
Not with this simplified energy-only model.
Should equipment degradation be included?
Run a separate conservative case with lower annual kWh savings because this page holds them constant.
What rate belongs in the model?
Use the marginal avoidable energy rate, excluding fixed charges and benefits that the project cannot change.