Dryers are sold in both electric and gas-fired models. The drying process consists of tumbling clothes, heating, and airing them. While gas dryers generally use less energy than electric models, and therefore are less expensive to operate, gas dryers usually require a higher first cost to buy and install. This is because gas dryers require both a gas line and vent pipe to the outside.
Also, older gas models may have continuously operating pilot lights, which waste energy. Newer gas dryer models must have electronic ignition systems rather than pilot lights.
When considering the purchase of a new dryer, look for the feature of a dryness sensor that automatically turns the dryer off when it detects the desired level of dryness.
Different makers offer different types of sensors. Those that detect moisture in the drying drum seem to be the most effective, however they also have a higher price. Others that sense the exhaust air temperature are lower in cost and seem less accurate. Any sensor type is better than no sensor or just using a timer. Energy savings on the order of 10 to 15 percent are typical.
If you remove still slightly damp clothes it will reduce the need for ironing which will also lower your energy use. Other reasons for not over drying clothes include reducing static electricity and shrinkage plus increasing fabric life.
Separate your clothes into light and heavy weight fabrics as the lighter weight ones dry quicker, while heavier weight ones take longer. Separating before drying lets you dry the first load and then take advantage of the already heated drum for drying the next load.
Accumulate laundry when possible so you can wash and dry full loads. In many cases you may have a matched washer and dryer, so a full washer load will also be a full dryer load.
Take care you do not overfill either the washer or the dryer. Washing and drying small loads wastes energy and overloading causes other problems.
Clean the dryer exhaust vent periodically of accumulated lint.
The exhaust vent hood flapper valve should also be checked to ensure it opens and closes freely. Otherwise unconditioned outside air will enter the house through the dryer vent, increasing your heating and cooling costs, not to mention allowing insect access.
Follow the maker's instructions and clean the dryer lint filter before each load. Restricted air flow from a clogged filter can be a fire hazard, while also reducing a dryer's performance.
When weather and local restrictions permit, hang your clothes outdoors and use free solar energy.