Calculator inputs
Fill the form and press calculate. Results appear above this form.
Example data table
Use this sample to understand typical entries and outputs.
| Scenario | Baseline | Rates | Usage | Heat Pump | Estimated yearly savings |
|---|---|---|---|---|---|
| Apartment family | Electric, 3.3 kWh/cycle | ₨ 60/kWh | 6 cycles/week | 1.5 kWh/cycle | ₨ 33,696 |
| Busy household | Electric, 4.0 kWh/cycle | ₨ 55/kWh | 10 cycles/week | 1.6 kWh/cycle | ₨ 68,640 |
| Gas baseline | Gas, 0.22 therm + 0.4 kWh | ₨ 4,500/therm, ₨ 55/kWh | 6 cycles/week | 1.5 kWh/cycle | Varies by fuel prices |
Formula used
Annual cycles
cycles_per_year = cycles_per_week × weeks_per_year
Energy cost
electric_cost = kWh_per_cycle × cycles_per_year × electric_rate
gas_cost = therm_per_cycle × cycles_per_year × gas_rate
Annual savings
baseline_annual_cost = baseline_energy_cost + baseline_maintenance
heatpump_annual_cost = heatpump_energy_cost + heatpump_maintenance
annual_savings = baseline_annual_cost − heatpump_annual_cost
Payback and lifetime
net_premium = max(price_premium − rebate, 0)
payback_years = net_premium ÷ annual_savings (if savings > 0)
lifetime_savings = (annual_savings × life_years) − net_premium
Emissions (optional)
baseline_co2 = (baseline_kWh × elec_factor) + (baseline_therms × gas_factor)
heatpump_co2 = (heatpump_kWh × elec_factor)
co2_saved = baseline_co2 − heatpump_co2
How to use this calculator
- Pick your baseline dryer type (electric or gas).
- Enter your cycles per week and local utility rates.
- Use your manual label or estimate kWh per cycle.
- Enter heat pump kWh per cycle from a product spec.
- Add price premium and any rebate to estimate payback.
- Open advanced options for maintenance and emissions.
- Press Calculate. Download CSV or PDF if needed.
Efficiency and savings benchmarks
Typical energy use per drying cycle
A conventional electric resistance dryer often lands around 2.5–5.0 kWh per cycle, depending on load size, moisture level, venting, and sensor accuracy. Heat pump models commonly fall near 1.0–2.0 kWh per cycle because they recycle warm air instead of constantly creating new heat. The calculator multiplies your chosen kWh per cycle by annual cycles to show the impact of small efficiency differences over a full year.
How utility rates shape annual cost
The same dryer can look “cheap” or “expensive” based on local electricity pricing. If your rate increases by 10 per kWh in your currency, yearly operating cost rises by that 10 times annual kWh. For gas baselines, therm pricing can dominate the comparison, while electricity may still matter for controls. Use your bill’s unit rates, not total invoice amounts, to keep the estimate consistent.
Payback depends on premium and usage
Payback is calculated as net premium divided by annual savings, so rebates can shorten payback immediately. Household usage is the next driver: more cycles per week usually means more potential savings, especially if the heat pump kWh per cycle is much lower than your baseline. If savings are negative, payback is shown as N/A, signaling that energy or maintenance assumptions should be revisited.
Lifetime savings and replacement planning
The net lifetime figure estimates total benefit over your selected service life by multiplying annual savings by years, then subtracting the net premium. This helps compare options when you are already replacing a failing dryer. If your dryer lasts 10 years and saves 30,000 per year, that is 300,000 before premiums. Adjust life years if you expect heavier wear, frequent moves, or harder water affecting maintenance.
Emissions impact and household reporting
Emissions are optional and depend on the factors you enter. Baseline CO₂ equals baseline electricity times the grid factor plus baseline gas therms times the gas factor. Heat pump CO₂ uses electricity only. If your grid is cleaner or you purchase renewable electricity, the CO₂ savings increase. These outputs can support home upgrade tracking, sustainability reporting, or simple “before and after” comparisons.
FAQs
1) Where do I find kWh per cycle?
Check the energy label, manufacturer specification sheet, or a plug-in energy meter. If you only have annual kWh, divide by your estimated annual cycles to approximate per-cycle use.
2) What if my dryer loads vary a lot?
Use an average cycle based on your typical week. If you mix heavy towels and light clothing, pick a mid-range kWh per cycle or run two scenarios and compare the results.
3) Why is payback shown as N/A?
That happens when annual savings are zero or negative. Review utility rates, baseline energy assumptions, and heat pump kWh per cycle. Maintenance costs can also shift the comparison.
4) How should I enter gas dryer electricity use?
If you know it, enter a small baseline kWh per cycle (often below 1.0). This captures motor and controls. If unknown, you can leave it at the default and focus on therm usage.
5) Does line-drying change the estimate?
Yes. Reduce cycles per week or weeks per year to match the months you air-dry. Lower usage reduces annual cost for both dryer types and may lengthen payback.
6) Are the emission factors universal?
No. Grid electricity varies by region and time, and gas factors can differ by reporting standard. Replace defaults with your local utility or government values for more accurate CO₂ results.