| Switchable glazings can help reduce energy usage. | | | | Solar powered windows go a step further, |
| Switchable glazings can lower energy costs for | | | | requiring no purchased electricity to operate the |
| cooling a home by reducing direct solar gains, | | | | windows whatsoever. In either case, |
| especially in the summer. They can block UV rays | | | | electrochromic windows do not make any other |
| and radiant heat (particularly useful for skylights) | | | | energy demands during their lifetimes – just |
| and lower cooling loads. In cooler northern | | | | what's necessary to make the switchable glazings |
| climates, electrochromic windows can effectively | | | | functional. |
| eliminate the need for mechanical air cooling | | | | What are the downsides to switchable glazings |
| systems altogether. | | | | and electrochromic windows? |
| By decreasing the solar heat gains, electrochromic | | | | Electrochromic windows can reduce energy usage |
| windows can also help eliminate the need for | | | | and sun damage, but they are complex windows |
| window coverings such as shades or blinds. That | | | | that aren't exactly a piece of cake to install. |
| means that homeowners can not only enjoy their | | | | Electrochromic windows that utilize electricity |
| surroundings more (keeping a room comfortable, | | | | require a non-standard electrical hookup and |
| and not too hot), but they can also enjoy their | | | | unconventional wiring (including a switch). That |
| views during the day. | | | | means that homeowners may have to hire an |
| Switchable glazings can also protect a home's | | | | electrician as well as a window installer, or a |
| interiors from damaging UV rays, so that carpets, | | | | general contractor or other tradesman who can |
| furniture, and artwork don't experience fading | | | | handle all facets of installation. |
| from the sun. Electrochromic windows also offer | | | | Switchable glazings are commercially available, but |
| more control than windows that are photochromic | | | | inconsistently. Few can be found at major retailers |
| or thermochromic (these are windows that turn | | | | such as home improvement stores. Some are for |
| opaque when exposed to light or warm | | | | residential use only, some are only available |
| temperatures). | | | | through the manufacturer or select vendors, and |
| While many might think that the electricity | | | | so on. |
| required to operate the switchable glazings is a | | | | Probably the biggest disadvantage of all is the |
| negative attribute, manufacturers and supporters | | | | cost. Electrochromic windows cost significantly |
| point out that the energy required to run the | | | | more than a standard window, as much as 2 to 3 |
| windows is minimal. Low-voltage products use less | | | | times more. Liquid crystal glazing can add as much |
| power than line voltage products. Plus, they use | | | | as $90 per square foot to the glazing! As with |
| virtually no energy to maintain a clear state. | | | | most 'new' technologies, the price point for these |
| Moreover, the energy that is saved by reducing | | | | high-tech windows is expected to drop to more |
| cooling needs and energy expenditures far | | | | reasonable levels as supply and demand increase, |
| outweighs the energy use by electrochromic | | | | technology improves, and manufacturing becomes |
| windows. | | | | less involved. |