Know how light mixes with the trees around your property. You may think you've got the perfect spot for a solar panel, but watch it throughout the day. The sun coming in from different angles may lead to surprising shadows from trees and foliage. This will affect your solar output.
Heliocol customer Keith Gascoine in Tallebudgera, QLD reviews his happy experience using Heliocol solar pool heating.
Try using a clothes line to dry your clothes. This is an older idea that works just as well. Rather than drying clothes in the dryer, hang them outside on nice days. This will save energy, which in turn will save money.