On my toilet tank, instead of just a lid, I have simple system that directs all fresh water thru a tall tap and then, thru a drain, into the tank for the next flushing. I wash my hands in this water during the flushing refill of the tank and the "grey water" from my hand washing becomes my flushing water. Also have an adjustable volume valve in the tank to reduce flushing volume. Low flow, but, relatively high pressure, shower heads are available, as are aerator attachments for the kitchen tap that reduce the volume of water used to wash dishes/hands/vegetables. Rain water catchment is easy and not very time consuming if camping in wet weather. "Sun shower" systems are a cheap and easy way to have a hot shower outside and not use any electricity to bathe. A relatively small photovoltaic system (200 watt panel, 2 12volt storage batteries, small charge controller, and small inverter, using big guage wiring) can run all entertainment gear(small flat screen tv, laptop, phone charger, radio, etc.),led lighting, and fans. Solar charged flashlights, radios, and fans are now pretty cheap and functional. Using bicycles or electric assist bicycles while camped instead of always using your car/suv to run small errands and go on short distance sight-seeing excursions will reduce fuel consumption and add simple pleasure and exercise. Needless to say, fully inflated tires and conservative driving will reduce fuel needs too.