If we chat about saving energy, topics such as insulation, or electric cars, might arise. If instead we chat about wasting energy, an entirely different set of issues comes to mind. I define waste as an expenditure without sufficient return in benefits. Obviously, benefits are subjective so that one man's waste is another man's essential. Exposing the diversity of opinions on these topics is my goal in posting this thread. Below, you will see my personal list for the most wasteful uses of energy in the USA. Some are more substantial, and others more symbolic. Some require us to do more than reach for a check book to be green, but rather to change our life styles substantially. Excessive speed: I would make the 55 mph speed limit ubiquitous and permanent. I think we should make all non-emergency vehicles have a limiting speed governor. Even a 45 mph speed limit sounds appealing. Clothes dryers: Ban clothes dryers, and return to outdoor clothes lines. Our parents and grandparents got along fine with clothes lines, winter and summer, city and country. There is no reason why we can't. Green grass: It takes energy and causes pollution to cultivate and to mow the grass and to provide the copious amounts of fresh water needed to keep it green. It takes energy to produce the chemicals we spread on grass, and more energy to remove the chemicals from the waterways. I see no reason why grassy areas can't be replaced by more sensible ground cover. Lights without people: To me, nothing seems more symbolically wasteful as a light shining someplace where it does not reflect into a human eye. Lighting efficiency should be measued by the percent of photons reaching a human eye. I would require all indoor and outdoor lighting to be controlled by a motion sensor. (Most motion sensors consume 1 watt or less. The best ones use only 0.2 watts.) Ideally, I would make the night view from satellites completely dark. Wall warts, and electronic devices in sleep mode waiting for a remote control to wake them up are very wasteful. Wikipedia says "...about 32 billion kilowatt-hours (kWh) per year, about 1% of total electrical energy consumption, could be saved..." 1% is huge; more than twice as much as total USA solar PV production. That 1% number may or may not be accurate, but the symbolic message of energy waste blares. At the very least, all sleeping devices should be attached to the same motion sensor that turns on the lights, and should consume zero power when the room is dark. Wall warts should consume zero energy when they are not supplying needed power to the device they serve. Commuting and low density housing: We could declare war on personal vehicles and free-standing structures. Encourage everyone to live within walking distance of their work and shopping (or to telecommute), and for companies to recruit employees only from the local neighborhood and from telecommuters. They would not need to own any personal vehicle, nor to depend on public transportation. They could also use district centralized heating/cooling which is much more efficient. Some European countries use heavy-handed building permit restrictions to force most of their population to live in high-density areas, and some countries are overtly hostile to personal vehicles. One could also make arguments about not living in places that require much heating or cooling or simply tolerating larger excursions of indoor temperature as our forefathers did. Vacation and business travel: I view the distances we go and the money we spend on vacation pleasure as consipcuous display of an overly affluent society. I also think that a large fraction of business travel could be replaced with a video conference, and that the benefit of face-to-face meetings is often insufficient to justify the travel. So, go ahead and trash my list. Post your own list.