The formula, without hidden cost
Estimated cost = price delivered + years × (annual kWh × €/kWh + other annual costs). For data in kWh/100 cycles: kWh per year = consumption × annual cycles ÷ 100. For data in kWh/1 000 hours: consumption × annual hours ÷ 1 000.
With average power in watts: annual kWh = watts × annual hours ÷ 1,000. The maximum power printed on an appliance does not necessarily describe its average consumption; use a measurement or an explicit assumption.
The period entered is a comparison horizon, not a promised lifespan. Other costs are your estimates: if water, consumables or maintenance are unknown, the result remains limited to your scenario. Do not count electricity a second time in this field.
Fictional example: an additional purchase cost may take years to pay back
A costs €400 and uses 200 kWh/year; B costs €500 and uses 150 kWh/year. At a fictional €0.25/kWh with no other costs over five years: A = 400 + 5 × 50 = 650 € ; B = 500 + 5 × 37,50 = 687,50 €. B uses less electricity but remains €37.50 more expensive over this period. Its €100 additional purchase cost is offset after eight years only if the assumptions remain constant.