Weatherization a home may consist of changing the light bulbs with low voltage bulbs, replacing the refrigerator or other low efficiency appliances, changing the HVAC compressor, sealing windows & doors, and insulating the walls. Please see link for complete Weatherization Check List
Solar
Photovoltaic energy is the conversion of sunlight into electricity. A photovoltaic cell, commonly called a solar cell or PV, is the technology used to convert solar energy directly into electrical power. Solar Panels will significantly lower your energy bills as well as lower your carbon footprint. Please see link for how solar panels work: Solar panels
Geothermal
While temperatures above ground change a lot from day to day and season to season, temperatures in the upper 10 feet of the Earth's surface hold a nearly constant temperature of 50 - 60 degrees Fahrenheit. In most areas, this means that soil temperatures are usually warmer than the air in winter and cooler than the air in summer. Geothermal heat pumps use the Earth's constant temperatures to heat and cool buildings. They transfer heat from the ground (or water) into buildings in winter and reverse the process in the summer.
According to the U.S. Environmental Protection Agency (EPA), geothermal heat pumps are the cleanest, most efficient form of energy, providing safe cost-effective systems for temperature control. Although, most homes still use traditional furnaces and air conditioners, geothermal heat pumps are becoming more popular. In recent years, the U.S. Department of Energy along with the EPA have partnered with industries to promote the use of geothermal heat pumps.
Wind
Air has mass and when it is in motion it can be harnessed and converted electricity. Harnessing the winds energy is typically done by installing a wind turbine. A wind turbine often is placed at the highest point with little or no interference.
A home can be served simultaneously by the wind turbine and a local utility. If the wind speeds are below 7-10 mph the turbine will not generate electricity and the needed power is purchased from the utility company. As wind speeds increase, turbine output increases and the amount of power purchased from the utility is proportionately decreased. When the turbine produces more power than the house needs, the extra electricity is sold back to the utility. All of this is done automatically. There are no batteries in a modern residential wind system. Read more at American Wind Energy Association
Grey Water
Any water that has been used in the home (except 'black water' which is from toilets and garbage disposals) is called grey water. Dishwasher, shower/tub, bathroom sink, and laundry water comprise 50-80% of residential "waste" grey water. This grey water may be reused for the toilet water and/or landscape irrigation. Grey water is not for drinking purposes. Grey water works like this: the wash water goes to a grey water tank is filtered and purified, the remaining water can be reused in toilets or in your garden. Reusing grey water will decrease water consuming and your water bill! Did you know that a person living by themselves can save over 20,000 gallons of water a year. A three person family can save over 38,000 gallons of water a year by reusing grey water.