SOLAR POWEREDHOT WATER

HEATERS

Sustainable Design Building System Research

PRODUCT & MANUFACTURERS

PRODUCT: Solar powered hot water heaters

MANUFACTURER: Silicon Solar

LINKS:

http://www.energysavers.gov/your_home/water_h

eating/index.cfm/mytopic=12850

http://www.siliconsolar.com/pre-packaged-shw-sy

stems.html

SOLAR COLLECTOR OPTIONS

FLAT PLATE COLLECTOR: This system consists of glazed, weatherproof boxes that contain an absorber plate and glass or polymer cover.

INTEGRAL COLLECTOR-STORAGE SYSTEM: Also known as ICS or batch systems. This system has one or more black tanks or tubes in an insulated, glazed box. Cold water first passes through the solar collector and is heated, then travels to a conventional backup water heater. This method is not recommended for extremely cold climates because of the risk of pipes freezing.

EVACUATED TUBE COLLECTOR: This system consists of parallel rows of transparent glass tubes. Each tube contains a glass outer tube and metal absorber tube attached to a fin. The fin's coating absorbs solar energy but inhibits heat loss. Most commonly used in commercial applications.

ACTIVE HOT WATER OPTIONS

DIRECT CIRCULATION SYSTEMS: Pumps circulate househould water through the collectors and into the home. Recommended for mild climates only.

INDIRECT CIRCULATION SYSTEMS: Pumps circulate a non-freezing, heat-transfer fluid through the collectors and a heat exchanger. This heats the water that then flows into the home. Recommended for colder climates.

PASSIVE HOT WATER OPTIONS

INTEGRAL COLLECTOR-STORAGE PASSIVE SYSTEM: Cold water first passes through the solar collector and is heated, then travels to a conventional backup water heater. Recommended for mild climates.

THERMOSYPHON SYSTEMS: Water flows through the system when warm water rises as cooler water sinks. The collector must be installed below the storage tank so that warm water will rise into the tank. These systems are reliable, but roof design should be taken into consideration to accommodate the heavy storage tank. They are usually more expensive than integral collector-storage passive systems.

MAINTENANCE & LIFESPAN

Solar hot water heaters should be installed with a conventional back-up hot water system to ensure function in cloudy weather and days with increased demand. Some systems will have a back-up system included in the package.

The proper installation of solar water heaters depends on the following factor: solar resource, climate, local building code requirements, and safety issues

Passive systems don't require much maintenance. For active systems, discuss the maintenance requirements with your system provider, and consult the system's owner's manual. Plumbing and other conventional water heating components require the same maintenance as conventional systems. Lifespan for solar heated hot water systems is similar to conventional systems, proper maintenance will increase longevity of the systems.

ADVANTAGES, END USER & COST

ADVANTAGES: Decreased costs to heat water by using a renewable, free, off-the-grid energy source. Multiple system options are available to meet climate and end-user requirements. Flexible installation options and integrated back-up systems allow for easy conversions from conventional to solar heating systems.

END USER: residential and commercial applications.

COST: Depends on system type – Active systems

ENERGY CREDITS & LONG-TERM BENEFITS

EXAMPLE IMAGES