For example, acid rain can increase the levels of toxic metals such as aluminum, copper and mercury in untreated drinking water supplies. Also, studies conducted in Canada and the U.S. indicate that there is a link between acidic particulates and respiratory problems. The goal of Environmental Defense is to cut the emissions that cause acid rain in half by using an emissions trading system. If a particular utility emits 5 tons of pollution annually, the EPA can tell them to reduce that to 4 tons the next year. Utilities must keep their emissions within their established allowances.
Utilities can earn more allowances by emitting less or buying allowances from another utility.
If the utility emits less than the allocated amount, it can save its leftover credits for future use or sell them. Reduce the amount of energy you use in your home. Turn off lights and electrical appliances when not in use. Purchase energy saving appliances. Purchase clean-running cars and maintain them so that they continue to run clean.