These mowers are quiet, convenient and demand almost no maintenance, yet the cost is similar to that for gas mowers. Use your dishwasher's booster heater to make up the difference. Also consider a high-efficiency water heater. While it may cost more upfront, it's worth it in the long-run. Look at lifetime costs, since energy costs account for more than 90 percent of the total cost of a water heater.
More people generate more heat.
Cook several dishes at the same time in your oven and leave the oven closed. The oven temperature drops 25 to 50 degrees every time you open the door. Use the oven light and window to check the progress. Use a pressure cooker or microwave when possible. Cooking with a regular pot takes three times as long as a pressure cooker and four times as long as a microwave.