Rated power draw is the wrong number for estimating a clothes dryer's electricity bill. What matters is energy per cycle multiplied by your marginal tariff rate — and among identically sized heat-pump dryers, that figure spreads by up to 1.7 times.
Condensing boilers list 92% or better heating efficiency against the mid-80s for standard units. Converted at Seoul's 22.5268 won per MJ gas rate, the bill gap narrows to 9.8%.
The litre figure on a Korean refrigerator is effective internal volume, and the efficiency grade is scored relative to that volume. In public filings, a 299L Grade 1 unit drew 4.9 kWh less per month than a 253L Grade 2 unit.
The power and water figures on a washing machine label are per cycle. At five washes a week you multiply by 260. A 100Wh difference per cycle costs 5,580 won a year; 20 litres costs 6,396 won.
Air conditioners are chosen by cooling capacity in kW, not floor area. The Korean standard is 400W per pyeong, with a 1.3x correction for living rooms.