Moisture brings durability and air quality problems with it, and myriad green products are designed to manage it and keep it out. Given the variety of products available, we look for those that meet key performance standards and that make sense in a whole building assembly—such as vapor-permeable weather-resistive barriers that not only prevent moisture from entering the building envelope but also allow drying when the envelope gets wet.
While resilience—the ability to weather natural disasters and maintain livable conditions in the aftermath of disruptive events—is mostly an issue of building design and community preparedness, certain products can help. For example, almost all heating systems require electricity to operate even if their primary fuel is oil, gas, or wood pellets; systems that allow operation even if grid electricity is not available are more resilient in the event of power outages. Rainwater harvesting, water storage, composting toilets, and waterless urinals contribute to resilience not only in drought-prone areas but also during power outages in any home dependent on well water. Solar water heating systems that can operate without utility power, and back-up power systems that are more energy-efficient than standard generators, may have this attribute.
The SunRay-30 and SunRay-1000 can provide inexpensive microbial water purification without electricity, pumps, chemicals, or boiling. The SunRay-30 is comprised of a black, double-walled HDPE collector covered by two layers of transparent acrylic glazing. Up to 3.5 gal. of untreated water is poured into the unit and placed in the sun; when pasteurization is complete, an indicator will change color. The SunRay-1000 is designed to purify approximately 260 gal. of water a day in sunny climates, utilizing a flat plate collector, a high-efficiency heat exchanger, and a fail-safe thermal control valve. On cloudy days, or at night, an optional backup burner can use any form of combustible fuel. Neither unit can be used in freezing temperatures.
Water filtration equipment is necessary in many areas to provide high-quality purified drinking water. In the U.S., 15% of households have their own wells, many in rural areas where agricultural runoff containing pesticide residue makes water purification an essential health measure. Worldwide, the number of people without access to clean drinking water is in the billions.
GreenSpec lists products using solar power, or passive solar distillation, processes which use renewable energy and that will work in off-grid situations or in the case of power outages. These systems can also be key components of rainwater harvesting systems.
GreenSpec does not currently list reverse-osmosis systems or water softeners, which introduce salt into wastewater. For more information, see The Water We Drink: Softeners, Filters, and Other Treatment Options in EBN.
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