February 20, 2007 4:00 AM PST

A sunny forecast for hot water

It's a solar power concept that was popular around the time Calvin Coolidge was president--but now it's poised for a comeback.

Solar thermal water heaters, which use solar energy rather than gas or electricity as a power source, could grow in popularity over the next few years, according to analysts and panel installation companies. While the idea has already caught fire in China, it's barely registered a blip in the U.S.

"The idea that we don't have solar thermal is crazy," said Bill Green, a partner at VantagePoint Venture Partners who specializes in clean technology.

Solar thermal heating

Interest, nonetheless, is beginning to percolate, said Alex Winch, president of Mondial Energy. Mondial installs solar thermal systems in large buildings and then makes its money by reselling the heat generated by them back to the building owner. The Toronto-based company has put systems in 100-unit senior living centers in Canada, and it recently signed letters of intent for installations in a couple of U.S. hotels.

Solar thermal systems can offset gas consumption even in places not known for sunshine, Winch noted. His first project was the Beach Solar Laundromat in Toronto. It's snowy in that city right now, but the system at Beach Solar has generated 382 kilowatts in the past week, according to its online energy meter.

"I'm in my office, and I'm literally looking at a snow bank that is four feet thick," Winch said. "The gas boiler gets water that is 10 to 20 degrees warmer than it ordinarily would be."

Solar hot water will likely be one of the topics discussed at the Cleantech Forum taking place in San Francisco in this week. The mushrooming conference serves as a launch pad for clean tech start-ups.

Partly driving the interest--besides global warming and rising energy costs--is the fact that the systems work quite well. It is far easier to extract heat from the sun than electricity, according to Gary Gerber, CEO of Sun Light and Power, which installs solar systems. Solar thermal heaters ultimately use about half of the heat that hits them; that makes them two to three times more efficient than the solar panels that turn sunlight into electricity.

Solar thermal what?
Solar thermal water heaters use a different technology than solar thermal electric (STE).

In STE, massive arrays of mirrors in the desert focus solar heat onto liquid-filled tubes. The liquid turns to steam, which spins a turbine to create electricity for distant metropolises.

They also aren't nearly as ugly as you might think. Although rooftop water tanks are used in some parts of the world, most homeowners tend to opt for systems where the tank stays downstairs. Metal and glass panels measuring 4 x 10 feet on the roof collect the heat. Rheem, Apricus and a variety of companies make the components that installers like Sun Light or Poco Solar subsequently install.

"We can usually provide 60 to 80 percent of a home's hot water with one or two 4-by-10-(foot) panels and a storage tank," Gerber said. A typical solar thermal system with a 120-gallon tank costs around $7,000 to $10,000, before a $2,000 federal rebate. The breakeven point for homeowners comes in 10 years or less.

Same old solar?
If solar thermal water heaters do make a comeback, it will be an example of history repeating itself. From around 1900 through the 1920s, solar thermal heaters were popular in places like Florida, Los Angeles and Berkeley.

Utility companies, however, persuaded consumers to switch to gas, even offering to swap out their solar heaters with free gas ones, according to Chris Beekhuis, chief technology officer at Fat Spaniel, a Mondial partner that provides monitors for the performance of solar electrical and thermal systems in homes and businesses. Solar largely disappeared over the next two decades, Beekhuis said.

Conspiracy theorists may point to history as another example of oil companies' underhandedness. Natural gas, however, was fairly cheap back then.

"No one was motivated to offset the price of gas," Beekhuis said. "Now it is an environmental issue and a cost issue."

In the vast majority of cases, property owners never completely divorce themselves from gas pipes. Solar heaters can't collect heat at night, after all. Winch, though, said the economic case can be made in more instances than one would think. Nunavut, in far Northern Canada, only gets 75 percent of the heat from the sun that Toronto gets. Yet gas there costs eight times as much, so solar thermal makes sense.

In sunnier areas, solar thermal can insulate large property owners from fluctuating gas bills. Under its contracts, Mondial agrees to sell its heat for a fixed rate for a 10-year period, and that rate is below the current cost of gas, Winch said.

China has already embraced the solar thermal concept. Approximately 80 percent of the capacity for solar thermal was installed in China in 2005, according to David Edwards, an analyst with investment bank ThinkEquity Partners. Overall, 60 percent of the world's solar thermal hot water capacity is in that country.

And in Israel, apartment buildings or condos with eight or fewer units must have solar thermal heaters. In cities like Jerusalem, you see a lot of the older rooftop tank systems.

Michael Eckhart, president of the American Council on Renewable Energy, added that the momentum in China could stunt any opportunities for U.S. companies to get into the market. Last year, China produced $3 billion worth of solar thermal products.

"When we were there (recently) manufacturers were asking whether they should export," he said. "The solar water industry is coming this way fast."

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12 comments

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Power v. energy
I assume Beach Solar has generated 382 kilowatt-hours in the past week (not kilowatts). You would hope that a technically-oriented website like CNET would know the difference between power and energy.
Posted by Jim1900 (821 comments )
Reply Link Flag
They don't know the difference...
They post a lot of these "alternative energy" articles yet most are
riddled with gaping holes, technical half-truths, and inaccurate
terminology.

It's a shame most readers don't know the difference, and nobody
really seems to care too much about accurate writing these days.

One would think that if you're going to spend this much time
writing about such technical matters you'd hire at least one
editor with an adequate engineering background.
Posted by Sparky672 (244 comments )
Link Flag
Why not solar
Hello --

Here's why renewable energy struggles!

Somebody comes up with an extremely expensive solar hot water -- benefiting -- and who is really benefited -- it's somewhat like the ethanol scam.

In the New York Times for today, February 20, 2007, a news item: "A sunny forecast for hot water" by Michael Kanellos, for News.com New York Times (E-Mail) starts with:
"Published: It's a solar power concept that was popular around the time Calvin Coolidge was president--but now it's poised for a comeback. Solar thermal water heaters, which use solar energy rather than gas or electricity as a power source, could grow in popularity over the next few years, according to analysts and panel installation companies. While the idea has already caught fire in China, it's barely registered a blip in the U.S."

"The idea that we don't have solar thermal is crazy," said Bill Green, a partner at VantagePoint Venture Partners who specializes in clean technology.
And what is it:
"...... Partly driving the interest--besides global warming and rising energy costs--is the fact that the systems work quite well. It is far easier to extract heat from the sun than electricity, according to Gary Gerber, CEO of Sun Light and Power, which installs solar systems. Solar thermal heaters ultimately use about half of the heat that hits them; that makes them two to three times more efficient than the solar panels that turn sunlight into electricity."

"Solar thermal what? Solar thermal water heaters use a different technology than solar thermal electric (STE). In STE, massive arrays of mirrors in the desert focus solar heat onto liquid-filled tubes. The liquid turns to steam, which spins a turbine to create electricity for distant metropolises."

They also aren't nearly as ugly as you might think. Although rooftop water tanks are used in some parts of the world, most homeowners tend to opt for systems where the tank stays downstairs. Metal and glass panels measuring 4 x 10 feet on the roof collect the heat. Rheem, Apricus and a variety of companies make the components that installers like Sun Light or Poco Solar subsequently install.

"We can usually provide 60 to 80 percent of a home's hot water with one or two 4-by-10-(foot) panels and a storage tank," Gerber said. A typical solar thermal system with a 120-gallon tank costs around $7,000 to $10,000, before a $2,000 federal rebate. The breakeven point for homeowners comes in 10 years or less.
Frequently such devices have to have auxiliary heaters -- mostly electric -- so as to provide hot water during periods without sunshine. And that cost is not included -- Shame!

The trouble is that even at a tankless hot water heater -- cost maximum of $500 dollars -- that is 90% efficient -- energy speaking -- would immediately heat sufficient hot water for a shower using 1% of the cost of the usual unit for natural gas -- including renewable natural gas as CFR produces -- for $0.15.

Lets see -- assuming the $5000 -- after federal rebate -- then it would take 82 years (after the tankless hot water heater cost is deducted) of daily showers -- or for a family of 4 -- only 20 years to recoup the investment in a device that lasts -- how many years before replacement (in either case)?

Ask the folks in Miami about bathing with a simple gravity solar hot water heater -- do they still exist in Miami?

Again -- somebody sells something -- makes dollars -- and some government unit allows for a tax credit -- and everybody feels good. And the real renewable industries -- just another 'black eye'!

If you want to feel good -- use natural gas -- until CFR's renewable natural gas is available.

More tomorrow -- it is real renewables that are required -- and in this case without counting the energy required to make the solar device? And remember -- conservation is the starting point, but:
The State of Florida announced in summer 2003 a Governor's initiated program....... ".... to develop a Statewide Energy Plan: Energy Planning for Florida's Future". The report (now removed from the internet -- but I have a copy) contained this admonition:

"The prime source of funds to support advances in energy efficiency and renewable energy resources in Florida is controlled by private utilities, whose business objective is to maximize profits rather than to conserve scarce energy resources."

And Solar Hot Water Guys and the Ethanol Guys and The Administration and their EPA and the Petroleum Guys and the Local Governments, the Automobile industry ... and so on and so on! Their position: "You can't conserve as well as depend on renewable energy, etc., or it will ruin the American economy." Nonsense! That's not the innovative America I grew up in!
Best, Dick

Dick Glick, PhD
President
Corporation for Future Resources
1909 Chowkeebin Court
Tallahassee, Florida 32301
Phone: 850-942-2022
Fax: 850-942-1967
Email: dglickd@pipeline.com
URL: <a class="jive-link-external" href="http://CorpFutRes.com" target="_newWindow">http://CorpFutRes.com</a>
Posted by dglickdr (5 comments )
Reply Link Flag
7 to 10k
Payback in 10 years possibly for a big family. I estimate about $20 in gas for hot water for a single user. That puts payback in the 29 year range. I think I'll invest my 7 to 10K elsewhere. How about having a second unisulated tank with no heaters inline that could bring ice-cold winter water up closer to room temp before your gas unit tries to heat it?
Posted by stlwest (72 comments )
Reply Link Flag
no difference in the winter.
quote: "How about having a second unisulated tank with no
heaters inline that could bring ice-cold winter water up closer to
room temp before your gas unit tries to heat it?"

Your ice cold uninsulated tank would just be sucking warmth
from the surrounding air which must be made up by your
furnace. Net difference of heat exchanged is zero.

Any possible savings would only depend on differences in
efficiency between your water heater and furnace.

Of course in the summer time when you'd want to cool the air,
you'd see a savings of some sort.
Posted by Sparky672 (244 comments )
Link Flag
Makes a lot of sense around here
A real-world example

I live in Hawaii where the price of electricity is $ 0.30+ per kwh, and we heat with that. It makes a lot of sense here, the specifics are:

Price of system is ~about $6k
Less powerco $1000 rebate off the top
Less 30% from fed gov as tax credit
Less 35% from state gov ditto

The bottom line is that the net cost is ~$1600

Last month, the first full month for the system, was a fairly cloudy month and our electric bill was down $40. The payback period is around 32 months here with our electric prices and low-interest loans are easy to get for this purpose. Our electric prices are high but everyone else's might be too if the Tomahawks fly into Teheran.
Posted by Vornan29 (2 comments )
Reply Link Flag
Hot Water in Hawaii
Electricity is 30+ cents a KWH in Hawaii??? Seriously? You folks need nuclear power in a bad way. What is stopping you? You could have power delivered to your house for less than 15 cents. There must be a problem with the education system in Hawaii.
Posted by ed_dykes (9 comments )
Link Flag
You guys are so behind the times.
In the Mediteranean (Greece where I live) everybody heats the water using solar panels. Even on cloudy days I have enough hot water for a bath and I live in a flat in Athens. This has been happening here since the early 80's.
(It's cheap too. It costs less than 2000 dollars to stick it in and you get hot water for free even in the winter.)
Posted by jsargent (98 comments )
Reply Link Flag
Globalwarming Awareness2007
<h1><b><i><em><strong><a href="http://www.theycann.com/" title="globalwarming awareness2007">Globalwarming Awareness2007</a>
</strong></em></i></b>
</h1>
Posted by justgold79 (51 comments )
Reply Link Flag
Is the US in a time warp???
Solar water heaters is an old technology. Here is Puerto Rico cost the same as in Greece , around 2000. I get more than enough hot water from the sun.
I think the US is very far behind , not in creating green technologies but actually using them. Every year they come with bigger and less efficient cars while other countries (like Norway) are planning hydrogen highways. The US must wake up.
Posted by yacahuma (530 comments )
Link Flag
The faster we go the behinder we get
Had a fine tankless water heater for 20 years. Moved to New
Mexico, a place with some supposed enlightenness.
Conventional WH died in 3 1/2 years. Having gone to area solar
info meetings, I called a solar installer. Ha. A minimum of a
month to respond. I intended to do a roof panel preheating for
a storage tank &#38; tankless heater - supposedly around $2300 per
meeting info.

Not practical to have wife do without hot water for a minimum of
a month. So now have a same old, same old unit. And some
guy promotes his 7-10 grand unit? Enticing acceptance by
incrementally more favorable costs? Not. Then states tankless
unit at $500 maximum cost - just wrong.

An upstart solar panel firm here in Albuquerque trying to make
incremental improvements to panels attracted a visit by George
Bush, but says it is working on that "breakthrough" to match
higher performance of competitors in maybe 2 or 3 years while
sapping government grants. Hey, it's other peoples money -
yeah, taxpayers.

Where's the long awaited progress? Just more farce like ethanol
for farm state votes?

$2300 I wanted to go for, but couldn't get for a minimum of a
month. 7-10 grand, I surely don't want. Meanwhile tax breaks
expired for Toyota selling it's allotment of Priuses, now the
program will boost some of those minor league hybrid pickup
trucks with one MPG improvement. Oh please, that kind of
progress is bogus.
Posted by NM_Bill (59 comments )
Reply Link Flag
Don't fall for the tankless trap. After rebates solar water heaters pay for themselves in 3-5 years. Find out more here http://www.sunbelt-solar.com
Posted by Solardude7 (1 comment )
Reply Link Flag
 

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