They say the cheapest watt is the one you don't have to buy.  Using efficient equipment and mindful behavior we can significantly reduce our daily energy consumption.  The largest residential energy users are space heating and cooling, kitchen appliances, and water heating. 

Water Heater Emissions

Tankless Gas Water Heater:  1 ton CO2 Annual Emissions

Conventional Gas Water Heater:  2 tons CO2 Annual Emissions

Conventional Electric Water Heater:  6 tons CO2 Annual Emissions

The U.S. Department of Energy (DOE) has announced new Energy Star criteria for water heaters.  Solar water heaters with OG-300 SRCC certification will be Energy Star labeled.  These water heaters save 50% in energy use.

Insulating hot water pipes and cold pipes will reduce condensation.  It only costs $15-$30 and will result in $15-$40 saving per year.  It will also reduce green house gases by 400 to 1,000 lbs per year.  It will result in raised delivered water temperature of 2 to 4 degrees F.

Low flow shower heads cost $5 to $10.  A standard shower head uses 5-8 gallons per minute.  A low flow shower head only uses 2.5 gallons per minute.  Converting to low flow will save you $50 to $75 per year in water savings and $20 to $30 in energy savings.  It will also reduce green house gases by 160 to 250 lbs per year.

Repairing a leaking faucet can save you $5 to $30 per month.

Setting your water heater back to 120 -125 degrees and draining the sediment once a year costs nothing and can save you $15 to $30 per year and reduce green house gases by 400 to 800 lbs per year.

Installing a washing machine cold water filter costs $25.  It will save you $20 to $60 per year in electric costs and reduce green house gases by 500 to 1500 lbs per year.

Installing heat traps on your water heater to reduce the conduction of heat costs $30.  This will save you $15 to $30 per year and reduce green house gases by 400 to 800 lbs per year.

Installing a tankless water heater will increase efficiency by 20% from a gas type tank.  The cost of the system is $600 to $1,200 installed.