Air conditioning can be useful beyond summertime and help people in the spring too. For example, allergy sufferers and those with asthma benefit from their air being filtered during times when the pollen count is high. 21. If you are concerned about keeping your home cool and don’t want to rely strictly on your HVAC system, there are a number of proactive things you can do to reduce your electric bill. Planting trees on the south side of your home will block the hot summer sun.