Energy Arbitrage Calculator
The formula
What the energy arbitrage tells you
What a load actually costs to run over a year — watts-hours-to-dollars conversion for energy arbitrage, the arithmetic utility bills hide.
Calculation: kWh/yr = W × h/day × days ÷ 1000; cost = kWh × tariff. Enter your inputs and every substitution is shown below the result.
Reading the result
Compare devices by annual cost, not wattage: a 150 W always-on box can out-cost a 2 kW appliance used minutes a day.
Limitations and best practice
Duty cycle, not nameplate, decides bills — motor and heater ratings are peak, and compressors cycle well below it.
This calculator gives an estimate based on standard formulas; it is not professional financial, medical, legal or engineering advice. Verify anything you plan to act on with a qualified professional and your own records.
Frequently asked questions
Standby counts?
Solar changes the tariff?
Source & methodology
Basic electrical energy identity.
Energy Arbitrage: what this tool answers
You are counting something that matters — this tool counts it exactly, including the edge cases calendars hide. There are plenty of pages about Energy Arbitrage; almost none of them show the working. This one does: the formula, every input, a fully computed example, and a sensitivity analysis calculated live from this engine’s own defaults.
The number itself is the easy part. What takes judgement is knowing which inputs are facts in your situation and which are guesses wearing a decimal point — a distinction this page makes explicit for every field above.
Like most useful measures, Energy Arbitrage is a summary, and summaries hide as much as they reveal. The companion outputs and the input table are here to reopen what the headline compressed.
What makes a calculation page trustworthy is that its copy is derived from its own arithmetic: here annual energy = 1,448.9 kWh, recomputed every time a field changes, and the sensitivity section ranks the inputs that move the result — Power draw first, at ≈10.0 % of the headline for a ten-percent error either way in that input — which is the thread the rest of this guide pulls on.
Every input in Energy Arbitrage, and what it does to the answer
The engine implements a single stated model: kWh/yr = W × h/day × days ÷ 1000; cost = kWh × tariff. There is no hidden coefficient and no login-gated precision — the formula printed is the formula executed, which is also what makes the result citable.
Power draw (watts) (example value 158) is a numeric input whose unit is fixed by the label; a wrong unit is a wrong answer wearing a plausible disguise. This input feeds the formula directly; a defensible figure here is worth more than false precision anywhere else.
Hours per day (example value 14) is a plain measured quantity — the unit shown in the label is the unit the formula expects. Be precise about the boundary (exact date, start of month); time inputs decide the exponent in most formulas.
Electricity price ($/kWh) (example value 0) is a measured number in the unit named by the label; the formula does not convert for you. If your source quotes a figure before and after some deduction, decide which one the formula wants and be consistent for every field.
Days per year (example value 655) is a quantity rather than a category — precision here is cheap and worth having. If the period is partial, decide whether you mean elapsed or planned time and keep that meaning across every field.
The default Energy Arbitrage calculation, written out in full
Rather than describe the calculation, here it is end to end — every substitution in order, starting from the inputs above. Starting figures: Power draw (watts), Hours per day, Electricity price ($/kWh), Days per year. The endpoint of that chain is 1,448.9 kWh of annual energy, sitting in the “Serious load — one upgrade cycle pays for itself” band.
- kWh/yr = 158 × 14.0 × 655 ÷ 1000 = 1,448.9
- Cost = 1,448.9 × $0.16 = $231.82
Annual cost — $231.82. Read next to the headline, this is the figure that shows the shape of the trade-off.
Monthly cost — $19.32. Read next to the headline, this is the figure that shows the shape of the trade-off.
CO₂e at 0.4 kg/kWh — 580 kg. Compare it against the main result of 1,448.9 kWh before drawing conclusions.
Keep this worked example open while you enter your own figures: matching the shape of the substitution is the fastest way to spot a unit or convention mistake.
Scenario table: Energy Arbitrage at ±10 % and ±20 % of the key input
The honest version of any estimate is a corridor, and this one is cheap to produce: Energy Arbitrage was recomputed at 5 points along the dominant input, with every other field left untouched.
| Power draw setting | Annual energy |
|---|---|
| 80 % of the example value | 1,159.1 kWh |
| 90 % of the example value | 1,304.0 kWh |
| example inputs | 1,448.9 kWh |
| 110 % of the example value | 1,593.7 kWh |
| 120 % of the example value | 1,738.6 kWh |
Across 5 settings of Power draw, the result spans 1,159.1 kWh to 1,738.6 kWh. A decision that only works at one row of this table is a decision waiting for an input to move. Reproduce it in the form above by editing Power draw alone; the substitution steps will follow your figures exactly.
Where Energy Arbitrage is fragile — and where it is not
Generic advice says “it depends on your inputs”; this section says exactly how much. Each field was perturbed by ±10 % in isolation and the annual energy recomputed, so the ranking below is measured rather than asserted. It is the fastest honest answer to “what matters most in Energy Arbitrage?” — and it is specific to these defaults, because sensitivity moves with the starting point.
- Power draw: ten percent up gives 1,593.7 kWh, ten percent down gives 1,304.0 kWh — ≈10.0 % of the annual energy either way
- Hours per day: ten percent up gives 1,593.7 kWh, ten percent down gives 1,304.0 kWh — ≈10.0 % of the annual energy either way
- Nudge Days per year by ±10 % and Energy Arbitrage lands between 1,304.0 kWh and 1,593.7 kWh (sensitivity ≈10.0 %)
Power draw is the dominant lever here: ten percent either way moves the result by about 10.0 %, from 1,304.0 kWh to 1,593.7 kWh. Measure that input from a document rather than from memory, and Hours per day is effectively tied with it (≈10.0 % for the same nudge), so verify the pair together. Everything below that can stay approximate, which is a licence to stop chasing data that would not change the decision.
Reading the result: bands, zones and thresholds
A number on its own is trivia; a number against a range is intelligence. The verdict attached to the default calculation — “Serious load — one upgrade cycle pays for itself” — is one band on a ladder your own figure may sit somewhere else on. Before treating the band as fact, note its width: ten percent either way on Power draw already spans 1,304.0 kWh to 1,593.7 kWh. The practical reading rules: compare against your own history before comparing against other people; treat band boundaries as zones, not walls — one point on the wrong side of a threshold rarely changes a real outcome; and when a companion output contradicts the headline, believe the pair.
Placing this figure in context: calculators of this kind differ less in arithmetic than in what they choose to ignore. This one keeps Power draw (watts) explicit so that the omissions are visible rather than hidden in a preset.
How people get Energy Arbitrage wrong
Duty cycle, not nameplate, decides bills — motor and heater ratings are peak, and compressors cycle well below it. This calculator gives an estimate based on standard formulas; it is not professional financial, medical, legal or engineering advice. Verify anything you plan to act on with a qualified professional and your own records.
Using stale inputs. Energy Arbitrage is only as current as the numbers behind it — an estimate carried over from a previous season, rate table or report quietly biases every output. Re-measure the inputs first; that single habit fixes more bad Energy Arbitrage figures than any formula change.
Attention is also misallocated between fields. Having measured this engine, we can say where it belongs: Power draw first, everything else second.
A final trap is presentation: reporting Energy Arbitrage to more decimal places than the inputs support. The tool prints what the arithmetic gives; you should quote only what your least precise field justifies.
Energy Arbitrage verification checklist
- State, in one sentence, which convention each rate, unit or period in the form is using.
- Confirm the example values are plausible for your own situation before replacing them.
- Check Power draw before anything else: it is the measured dominant input, ≈10.0 % of Energy Arbitrage per ten percent.
- Compare the output against one published benchmark or a colleague’s independent estimate.
- Check that every field the formula needs actually arrived from a document, not from recollection.
- Repeat the ±10 % test on the inputs that matter and see whether the decision — not just the number — still holds.
Five steps from raw inputs to a figure you can defend
The tool does the arithmetic; the routine below is what makes the arithmetic trustworthy. Five steps, a minute total — and afterwards you will know not just what the number is, but which assumption produced it.
Step 1 — collect, then type. Everything this tool asks for is listed above (power draw (watts), hours per day, electricity price ($/kwh), days per year). Pull each figure from something you can point at — paperwork, a dashboard, a label — before touching a field. Guesswork at the input stage cannot be repaired at the interpretation stage. The test of a good estimate is not that it feels right but that it changes what you do.
Step 2 — start from the case you can defend. Enter pessimistic-but-honest figures first; the optimistic run is a ceiling, not a plan. A conclusion that holds on conservative inputs holds everywhere. A calculation you cannot explain to somebody else is a calculation you cannot defend.
Step 3 — play with the inputs on purpose. Ten percent up, ten percent down, one field at a time. Within a few minutes you will know this calculation better than most people who quote its results. If the verdict changes with a ten-percent nudge, report the nudge alongside the number.
Step 4 — stress before you commit. A decision that survives a ten-percent squeeze on its two biggest inputs needs no luck to be sound. One that does not survive is a decision about hope, not about arithmetic. If the verdict changes with a ten-percent nudge, report the nudge alongside the number.
Step 5 — record the context, not just the number. Note today’s date and the inputs alongside the 1,448.9 kWh output. Six months from now the context is what turns this figure into a trend. The fastest sanity test is to guess the answer first and see how far the calculation disagrees.
From calculation to decision: where Energy Arbitrage earns its keep
Most Energy disagreements are arithmetic disagreements in disguise. When Annual energy of 1,448.9 kWh sits on the table with its working shown, the conversation stops being about who sounds more confident and starts being about which input is wrong. Numbers are cheap to produce and expensive to retract; the extra minute is the cheapest insurance available.
Used properly this is a five-minute filter that saves weeks. Compute Energy Arbitrage, reject what fails, and only then bring in the expensive analysis for the survivors. The input you reach for first is usually the one you measured longest ago.
Nothing here is stored or transmitted, so the habit of checking is free: open the page, re-enter current figures, compare with the number you saved last time. Repeating a calculation with the same numbers proves only that the arithmetic is reliable — which is worth knowing.
The questions that come up most about Energy Arbitrage
What affects Energy Arbitrage the most?
Measured on this engine, Power draw is the dominant lever: moving it ±10 % shifts the annual energy across 1,304.0 kWh to 1,593.7 kWh — about 10.0 % of the headline, with Hours per day next at ≈10.0 %. The ranked list in the sensitivity section is computed live, not asserted from a template.
Do hours per day and power draw matter equally?
On these inputs, yes: the two measured within a rounding error of each other — ≈10.0 % and ≈10.0 % of the annual energy per ten-percent change. Treat them as one pair to verify together rather than ranking them.
What is a typical Energy Arbitrage?
With the example inputs on this page the result is 1,448.9 kWh, labelled “Serious load — one upgrade cycle pays for itself”. “Typical” varies with situation, which is why every result here ships with its verdict band and its sensitivity list: they turn one figure into a range you can locate yourself inside.
How do I calculate Energy Arbitrage by hand?
Use the stated model — kWh/yr = W × h/day × days ÷ 1000; cost = kWh × tariff — and substitute in the order the tool prints (it starts from kWh/yr = 158 × 14.0 × 655 ÷ 1000 = 1,448.9). On the example inputs the hand route lands on 1,448.9 kWh, exactly what the calculator shows. A spreadsheet reproduces it in two or three cells; doing it once by hand is what makes the automated answer trustworthy.
What happens to Energy Arbitrage if power draw changes by 10 %?
On these inputs a ±10 % change in power draw takes Energy Arbitrage to 1,593.7 kWh against the 1,448.9 kWh example — around 10.0 % of the headline. The same test on every other field is in the sensitivity section.
Is the Energy Arbitrage result of 1,448.9 kWh good or bad?
Neither, on its own — the label “Serious load — one upgrade cycle pays for itself” is the band this figure falls in for the example inputs, and your own inputs will place you elsewhere on the same ladder. Judge the number against your history and your alternatives, and remember that a ten-percent error in Power draw alone moves it by ≈10.0 %.
Is Energy Arbitrage auditable?
Yes — the printed steps are the audit trail: inputs, formula, and substitution. This is exactly what reviewers need to re-derive 1,448.9 kWh from your raw records.
Which emission/consumption scope does Energy Arbitrage cover?
Whatever your inputs encode — typically direct consumption at the meter. Broader scopes (embodied, upstream) require adding their own inputs; do not compare a narrow Energy Arbitrage against a whole-life figure.
Standby counts?
Yes — modern standby rarely exceeds 2 W but 24/7 loads accumulate; the calculator just needs the measured watts.
Solar changes the tariff?
Swap $/kWh for your effective rate; with net metering the export credit is the number to use.
Does this Energy Arbitrage tool store my numbers?
No. The entire calculation runs in your browser session; nothing entered above is transmitted or saved, which is the correct behaviour for sensitive Environmental & Sustainability figures and the reason you can re-run this page as often as you like.
Glossary for Energy Arbitrage
- Annual cost
- $231.82 in the default Energy Arbitrage calculation — one of the secondary figures an experienced reader checks before trusting the primary number.
- Monthly cost
- $19.32 on the example inputs — a companion figure printed beside the headline of Energy Arbitrage so that no result is read in isolation.
- CO₂e at 0.4 kg/kWh
- 580 kg for the Energy Arbitrage worked case; it sits next to the main result because it carries context the headline leaves out.
- Annual energy
- The primary output of this tool: 1,448.9 kWh for the default inputs, computed exactly from kWh/yr = W × h/day × days ÷ 1000; cost = kWh × tariff.
- Worked example
- The step-by-step substitution printed above, so the arithmetic can be re-derived by hand or in a spreadsheet.
- Verdict band
- The plain-language label — here “Serious load — one upgrade cycle pays for itself” — mapping the computed figure onto experience-based ranges for Environmental & Sustainability.
- Sensitivity (±10 %)
- How far the Energy Arbitrage moves when a single input is nudged ten percent either way; the ranked list on this page is computed live from this engine.
Methodology, sources and limits
The model is published arithmetic implemented exactly as written: kWh/yr = W × h/day × days ÷ 1000; cost = kWh × tariff. Source of record: Basic electrical energy identity. Specialist software layers extra coefficients on top of the same algebra; none are hidden here, and that transparency is what makes a disagreement traceable to a specific input instead of a black box.
Nothing here replaces a qualified professional, and nothing here is approximate either — the arithmetic is exact, and the honesty is in the inputs you supply. Nothing is smoothed, weighted or adjusted behind the scenes; where judgement enters, this page says so and names the input responsible.
What to do with your Energy Arbitrage next
Re-run whenever a start date moves — time calculations compound small shifts into large misses.
This page was written for people planning around a point or span in time, and the promise is that nothing above required trust. Bookmark the tool, re-run it whenever an input moves by more than a few percent, and keep the date with the number.