This is the forty-ninth issue of my free newsletter. Your feedback is most welcome!
EARTH & US: Honoring the Sun as Our Energy Source
Summer’s long days are here. Blueberries, service berries, huckleberries, black raspberries abound in sweet juiciness, even on trails through the woods. Everything is growing with amazing rapidity (especially the weeds in my garden!) taking advantage of the strong energy from the sun.
Giving homage to the sun—as we humans have done for centuries on the Solstice—feels more and more natural in the "great turning" from a destructive, fossil-fuel based economy and culture towards a way of life powered by the sun’s huge energy flow.
Solar Hot Water
Recently I heard an inspiring talk about solar hot water by Dave Hollister of Sundance Energy Systems. He reminded us that all other life forms on this planet except humans get their entire energy supply from the sun. And we humans have barely begun to tap this gigantic resource!
According to Hollister, solar thermal (unlike photovoltaics) is a fairly simple technology. And a $5000 solar hot water system produces more energy than a $10,000 photovoltaic system, thus paying for itself much faster in savings. Solar hot water collectors are the most widely used solar technology in the world, they are affordable, and they are a major way to offset global warming! The industry, which started in the 1970's, collapsed in the '80's due to loss of incentives and subsidies; also because big oil companies bought them up. Some of those early collectors were hastily promoted and didn’t work very well, giving solar hot water a bad reputation. Now, the technology is improved, more reliable, and making a comeback.
Hollister outlined the major types of solar hot water collectors in use today, from simplest to most complex:
55-gallon drum or standard hot water tank painted black on the roof. It can be enclosed (or not) in a "breadbox" insulated structure with a parabolic reflective surface behind it. Good for temperate latitudes, not where it freezes. They can have a backup heating element. (Earthaven has a couple of these "breadbox collectors," which are not used during winter months but work well the rest of the year. They are thus available for the guests who are most numerous in those seasons.)
Flat plate collector, best value, usable in the Southeast. It consists of a header (aluminum frame), a black absorber plate, attached copper tubes at the bottom, glass covered, and insulated. The collector pays for itself in around 2.5 years if it's replacing an electric heater; 5 years if replacing natural gas.
Evacuated tube collector, allows heat transfer via a transfer medium fluid (propylene glycol). It takes less space than the flat plate collector, and creates higher temperatures, but is more expensive.
A flat plate collector requires 1.5 gallons of storage per square foot of collector; it will produce 1,000 BTU's per square foot per day. The best size would be one where all of the heat would be used all the time, including in the summer, with a backup heating element for times of extended cloudiness or cold. Hence, 30 square feet of collectors (one 4x8-foot collector) is usually plenty for 1-2 people (in the Southeast). One BTU heats one pound of water by one degree. Hence, to take 50 gallons from 50 to 120 degrees requires about 30,000 BTUs.
The "solar exposure window" is key. Best placement is within 20 degrees of true south. Collectors can be placed either on a roof, or in a yard. 70% of the solar window is between 10 am and 2 pm.
I was excited to learn that solar hot water can also be used for space heating. I had heard of using solar-heated hot water in radiant floor heating coils, but this is only practical in a new building. However, solar hot water can also be used as a pre-heater in a forced-air furnace heat exchanger.
Questions for Visionaries
Summer, according to cross-cultural anthropologist Angeles Arrien, is the time of the visionary. To help develop our vision, so deeply needed at this time on our planet, she suggests we ask ourselves these questions:
1. Am I telling the truth without blame or judgment?
2. Where and when am I bringing forth my authentic self (and when do I abandon myself)?
3. What are my favorite songs? Which ones do I teach others?
4. Between the ages of four and twelve, what activities captivated me for hours?
5. What makes me laugh? What are my sources of fun?
6. What is my spiritual autobiography?
7. Where do I seek guidance?
8. What do I want to re-dream in my life, and how can I manifest more of my life dream?
May your authentic self shine forth this summer, bringing you much joy!
Cathy Holt
"My religion is kindness." -Dalai Lama
www.thekindnesscampaign.org
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