| An Affordable Heat-Pump Water-Heater Retrofit | | | | |
| | | | Heat-pump water heaters have always been a |
| The engineers at AirGenerate (previously | | | | good idea, but most efforts to design, build, |
| Beyond Pollution) appear to have done | | | | and market（from： them have failed. |
| something remarkable: create an affordable, | | | | With today's high energy prices, however, |
| effective, heat-pump water heater that can be | | | | consumers should be more receptive to |
| retrofit onto a conventional gas or electric | | | | heat-pump water heaters, according to Harvey |
| water heater(from: more than doubling the | | | | Sachs, Ph.D., the buildings program director |
| energy performance compared with a standard | | | | at the American Council for an |
| electric water heater. The AirTap A7 water | | | | Energy-Efficient Economy. "The economic |
| heater has a rated output of 7,000 Btu/hour | | | | savings potential is so much greater than |
| (7.4 MJ/hour), a first-hour rating of 42.5 | | | | before, with the run-up of energy prices," |
| gallons (160 l), a maximum water temperature | | | | Sachs told EBN. |
| of 135°F (57°C), an efficiency of 240% | | | | |
| (coefficient of performance of 2.4), and an | | | | AirGenerate initially produced its AirTap A7 |
| energy factor of 2.11. (Energy factor is a | | | | water-heater kit in Houston, Texas. After |
| standardized measure of performance of water | | | | selling a few hundred units in late 2007, the |
| heaters; the higher the number, the better.) | | | | company began sourcing the product from an |
| All this is in a unit that measures only 18" | | | | offshore supplier. The outsourcing of |
| wide by 14" deep by 14" high (460 x 360 x 360 | | | | production will allow the company to |
| mm), weighs only 48 pounds (22 kg), and sits | | | | significantly ramp up production. The first |
| on top of a standard water heater. The list | | | | of the new (offshore-manufactured) AirTap |
| price is $499. The energy factor and | | | | units were received in January 2008, and |
| first-hour rating of the AirTap are certified | | | | about 200 had been sold through May 2008. Of |
| by GAMA (previously the Gas Appliance | | | | 400 units scheduled to arrive in June, almost |
| Manufacturers Association and now a broader | | | | all were pre-sold by the end of May, |
| association of appliance and equipment | | | | according to Sunil Sinha, chief scientist at |
| manufacturers). | | | | AirGenerate. |