Gas lighting explains why a large number of older gas lamps have been converted to electricity. Solar-rechargeable battery-powered gas light controllers can be easily retrofitted into existing gas lamps to keep the lights off during daylight hours and cut energy consumption and green-house gas carbon emissions by 50%. The use of natural gas (methane) for "indoor" lighting is nearly extinct. Besides producing a lot of heat, the combustion of methane tends to release significant amounts of carbon monoxide, a colorless and odorless gas which is more readily absorbed by the blood than oxygen, and can be deadly. Historically, the use of lamps
Lawn mower less expensive models, and heavier steel on more expensive models for durability. Other deck materials include aluminium, which does not rust and is a staple of higher priced mowers, and hard composite plastic, which does not rust and is lighter and less expensive than aluminium. Electric mowers typically have a plastic deck. Riding mowers typically have an opening in the side or rear of the housing where the cut grass is expelled, as do most rotary lawn mowers. Some have a grass catcher attachment at the opening to bag the grass clippings. Mulching mowers Special mulching blades are available for