Find Energy-Efficient Product Retailers ENERGY STAR® certified LED specialty light bulbs use up to 80% less energy and last up to 25 times longer than conventional incandescent lighting. Ameren Illinois offers discounts on these light bulbs for your home through participating retailers. ENERGY STAR appliances can also significantly reduce your electric bills. On average, home appliances – including water coolers, air purifiers and dehumidifiers – will account for 20 percent of your home’s total electric bill. To find a retail store in your area that carries qualified energy-efficient products, search by your zip code.