The Canada Mortgage & Housing Cooperation put out a great article about greening your home.
1. Insulate your walls. Sounds simple enough but living in an older home sometimes can have little or no insulation. Insulating your walls can save a ton of money in your heating bills.
2. Let your house breath! Newer homes are quite tight. In the summer you can crack a window but it may be harder in the wintertime to get fresh air into your home. Consider a heat recovery ventilator, or HRV.
3. Did you know you can capture heat from your wastewater – this can save energy and money
4. A home that is south facing windows can maximize heat during the winter. If you home is well insulated it can help keep that heat in better. Look up passive solar designs.
5. You can use rainwater that comes off your roof. Store in a barrel. You can use this water for your garden, lawn and even attach a hose for easy spraying.
6. Save on your electricity bill by unplugging items that you arent using. If you plug your electronics onto a power bar it makes it even easier to turn of the electricity to those units completely all at once. If buying new, look for the EnergySTAR symbol.