11.   But a quick glance at patents issued in the last several years reveals little new in the way of alternative fuels for running vehicles or heating houses.

12.   But at least your house is heated with natural gas, not oil.

13.   Consumption is also buying fuel to heat a house, or using an orthopedic surgeon or a nursing home.

14.   Houses were heated by wood-burning stoves or coal-burning furnaces that required constant attention.

15.   In addition to heating the house, Gifford said, the boiler also heats the domestic water for the building.

16.   It will generate power as well as heating my house and producing hot water.

17.   Q. My house is heated by steam, and on very cold days it is too hot upstairs and too cool downstairs.

18.   Residential users tend to rely on electricity more in the summer to operate cooling systems and on natural gas in the winter to heat their houses.

19.   She knows that when all the gas stove burners are on, her mother is trying to heat the house.

20.   That hot gas is used to preheat water going to the water heater, as well as air to heat the house.