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M II A II R II K Sep 28, 2009 1:44 PM

Solar Power Thread
Should you retrofit your home with solar power?

Cost of system not cheap but it will pay for itself quickly.

The short answers are: Probably (for your hot water heater); definitely (for your pool -- I know, summer's a distant memory); and likely not (for your household electrical needs).

Your hot water heater is an energy hog, accounting for up to one-quarter of your household's energy consumption.

Add greenhouse gas emissions associated with conventional hot water heating -- between 600 and 760 kg a year, according to the Ontario Ministry of Energy -- and endlessly renewable, non-polluting sunshine seems a no-brainer.

"From April to September, solar power will cover 90 per cent of your heating," says Michael McGahern, whose company, Ottawa Solar Power, sells, installs and services solar hot water systems. "From June to September, it'll be 100 per cent."

Factor in cloudy days and cooler temperatures through the balance of the year and a solar power system will meet 50 to 60 per cent of your annual hot water needs.

A system for a family of four runs around $6,500, according to McGahern. With federal and provincial grants and rebates factored in, the system should have paid for itself in seven to eight years, he says. But if energy prices increase, as some predict they will, it should pay for itself more quickly than that.

A solar hot water system for a family of four needs a couple of glycol-filled collector panels installed, preferably on a south-facing roof.

Heavily insulated copper pipes carry the heated glycol from the panels down the outside of the house and into the basement, where a new hot water tank with a heat exchanger feeds your existing unit.

When the sun shines, your hot water's free; when it doesn't, your electrical or gas-fired tank kicks in.

For optimal operation, the panels need direct sun from 10 a.m. to 2 p.m. every day, says McGahern, although the storage tank does hold the heat for up to 24 hours. The water is hottest in late morning and early afternoon.

Installation involves a couple of technicians clambering over your roof and through your basement for about a day and a half. You'll also need a municipal building permit.

"The single best use of solar energy is heating your pool," says McGahern. "It can pay for itself within a year, a year and a half."

A system runs between $3,000 and $5,000 and, like conventional pool heating, extends the swimming season by two to four weeks at both ends. These systems typically work by pumping the pool water through solar panels. Like other systems, components are usually long lasting and low maintenance.

As to solar-generated residential electricity, McGahern says, "People putting in those systems are doing it from an environmental point of view, not an economic one."

A typical Canadian household consumes 20 to 30 kWh of electricity a day, while even an ultra-efficient home uses three to six.

According to the experts, a solar-based electricity generating system with its array of sun-tracking photovoltaic panels, energy inverters and batteries will cost $30,000 and up for every 3 kW it produces.

What's more, homeowners usually have a generator or stay hooked to the hydro grid for those back-to-back days of cloud cover.

McGahern faults Canadian governments for short-sightedness in not subsidizing solar technology as some European countries do.

"Through subsidies, they've spawned a multibillion-dollar industry which is feeding those countries. They developed a tremendous amount of knowledge which is going to benefit all of us 10 years from now."

Canada Mortgage and Housing Corp. ( and Natural Resources Canada ( are good sources of information on most things solar.

Quallium, an Ottawa-based startup company, has installed solar electricity systems for clients hungering to go off-grid.

The systems are especially practical for cottages far from hydro lines, company owner Paul Fritz-Nemeth says.

He adds that a $5,000 to $10,000 system can provide backup for critical household circuits to run furnace pumps and other basic equipment during a power failure.

Not all solar panels are created equal, so it's best to ask about tolerance variations: A good 100-watt panel will generate 95 to 105 watts; take a pass on the one that bottoms out at 75 watts.

"The real problem is our habits," says Fritz-Nemeth. "Big-screen TVs consume a lot of power, especially when they're left plugged in all the time.

"People think the cost of solar systems depends on the size of their house. It really depends on what your habits are."

You Need A Thneed Sep 28, 2009 3:25 PM

A link to a competely solar powered house in Edmonton.

202_Cyclist Sep 28, 2009 3:33 PM

The US Dept. of Energy Solar Decathlon will be held in DC from Oct. 9-13, 15-18, 2009. Teams from universities in the US and abroad compete to design, build, and operate attractive solar-powered homes over one weekend. Here is the link for more information:

M II A II R II K Sep 29, 2009 4:24 PM

When this becomes mainstream I'm sure they'll have a tax on them and encourage people to rent out the equipment if they can't own them.

Krases Sep 30, 2009 1:16 AM

My parent's want me to help design a house for them when they eventually move out of there current home. They want solar power and a rainwater collection tank.

M II A II R II K Oct 12, 2009 10:33 PM

Inflatable Solar Panels Zip Together To Power Most Anything
Inflatable Solar Panels Zip Together To Power Most Anything

This lightweight, inflatable solar panel concept brings renewable energy access to any building and without that pesky renovation.

Each eye-shaped piece has a white foam shell that measures 4 feet by 2.5 feet. Inside the foam housing is an inflatable polymer lined with thin-film solar cells printed on mylar. The pieces can then zip together for a variety of configurations.

In lieu of costly renovation for conventional panels, the configurable pieces would provide easy solar-power access to most any building . The foam housings can be strung with wire or structural tubing to meet the needs of any structure.

The pieces could also be used for completely off-grid temporary structures.

smurf Oct 13, 2009 2:20 AM

The sad reality is that until PV technology takes a huge leap forward, PV solar is basically useless. There simply isn't enough power from the sun that reaches the ground. It works on a small scale, but it'll never work on a large scale. The best options are the parabolic mirror arrays that concentrate the sunlight and even then you get a paltry 16MW for a 1600acre site.

M II A II R II K Oct 13, 2009 5:14 PM

Florida to Build First Solar Powered City in U.S.

The eco-city, called Babcock Ranch, is a joint venture between a real estate developer, Kitson & Partners, and Florida Power & Light, and will be located near Fort Myers, Florida.

Babcock Ranch will include almost 20,000 houses and 6 million square feet of mixed retail, office, and light industrial space, and have city-wide wireless internet and electric car charging stations throughout.

The city will be fully powered by solar during the day, and produce an excess of electricity that will be exported to the grid. The CEO of Kitson said the project will serve as a model to other communities and be a “living laboratory for companies, workers and families ready to reap the rewards of innovation.”

Florida Power & Light expects to break ground on the $400 million solar PV plant this year, pending regulatory approval. Construction of Babcock Ranch is slated for the summer of 2010.

The project’s cost is estimated at $2 billion, and is expected to create 20,000 jobs.

Image: markus941 at Flickr under CC License

Nowhereman1280 Oct 13, 2009 7:05 PM

Can we get a similar thread for Wind Power Developments? I think it would be interesting to have one like the Boom Rundowns that keeps track of all the new wind farm developments across the country. They've built a ton of new wind farms in Wisconsin lately but I'd like to see whats going on in the rest of the country.

M II A II R II K Oct 15, 2009 8:27 PM

First black hole for light created on Earth
First black hole for light created on Earth

An electromagnetic "black hole" that sucks in surrounding light has been built for the first time.

The device, which works at microwave frequencies, may soon be extended to trap visible light, leading to an entirely new way of harvesting solar energy to generate electricity.

A theoretical design for a table-top black hole to trap light was proposed in a paper published earlier this year by Evgenii Narimanov and Alexander Kildishev of Purdue University in West Lafayette, Indiana. Their idea was to mimic the properties of a cosmological black hole, whose intense gravity bends the surrounding space-time, causing any nearby matter or radiation to follow the warped space-time and spiral inwards.

Narimanov and Kildishev reasoned that it should be possible to build a device that makes light curve inwards towards its centre in a similar way. They calculated that this could be done by a cylindrical structure consisting of a central core surrounded by a shell of concentric rings.

There's no escape

The key to making light curve inwards is to make the shell's permittivity – which affects the electric component of an electromagnetic wave – increase smoothly from the outer to the inner surface. This is analogous to the curvature of space-time near a black hole. At the point where the shell meets the core, the permittivity of the ring must match that of the core, so that light is absorbed rather than reflected.

Now Tie Jun Cui and Qiang Cheng at the Southeast University in Nanjing, China, have turned Narimanov and Kildishev's theory into practice, and built a "black hole" for microwave frequencies. It is made of 60 annular strips of so-called "meta-materials", which have previously been used to make invisibility cloaks.

Each strip takes the form of a circuit board etched with intricate structures whose characteristics change progressively from one strip to the next, so that the permittivity varies smoothly. The outer 40 strips make up the shell and the inner 20 strips make up the absorber.

"When the incident electromagnetic wave hits the device, the wave will be trapped and guided in the shell region towards the core of the black hole, and will then be absorbed by the core," says Cui. "The wave will not come out from the black hole." In their device, the core converts the absorbed light into heat.

Quick work

Narimanov is impressed by Cui and Cheng's implementation of his design. "I am surprised that they have done it so quickly," he says.

Fabricating a device that captures optical wavelengths in the same way will not be easy, as visible light has a wavelength orders of magnitude smaller than that of microwave radiation. This will require the etched structures to be correspondingly smaller.

Cui is confident that they can do it. "I expect that our demonstration of the optical black hole will be available by the end of 2009," he says.

Such a device could be used to harvest solar energy in places where the light is too diffuse for mirrors to concentrate it onto a solar cell. An optical black hole would suck it all in and direct it at a solar cell sitting at the core. "If that works, you will no longer require these huge parabolic mirrors to collect light," says Narimanov.

M II A II R II K Oct 22, 2009 1:24 PM

'Major discovery' from MIT primed to unleash solar revolution

Scientists mimic essence of plants' energy storage system

In a revolutionary leap that could transform solar power from a marginal, boutique alternative into a mainstream energy source, MIT researchers have overcome a major barrier to large-scale solar power: storing energy for use when the sun doesn't shine.


You Need A Thneed Oct 22, 2009 8:25 PM


Originally Posted by M II A II R II K (Post 4517929)
'Major discovery' from MIT primed to unleash solar revolution

Scientists mimic essence of plants' energy storage system

In a revolutionary leap that could transform solar power from a marginal, boutique alternative into a mainstream energy source, MIT researchers have overcome a major barrier to large-scale solar power: storing energy for use when the sun doesn't shine.


While cool, I don't know how this relates to solar power, really. Sure, it would work well with solar power as a method to store energy, but what is REALLY needed before solar power takes off is more efficient solar panels. It's expensive to get enough power for daytime needs, never mind to store up power for nighttime needs.

M II A II R II K Oct 23, 2009 7:55 PM

It Takes a Solar Village

October 19th, 2009 Joe Verrengia

Team Germany's winning "Cube House" featured silicon and thin-film solar panels on all visible sides of the house. The design's solar panel operates a toy on the front porch of the home. Credit: Stefano Paltera/U.S. Department of Energy Solar Decathlon

( -- Rain didn't ruin the 2009 Solar Decathlon in Washington, D.C. University teams successfully operated 20 net-zero, grid-connected solar power homes for a week on the National Mall. Some used more power-generating solar panels; others relied on energy efficiency strategies. The winner was clean energy.

Rain usually spoils a solar power contest. But three days of showers — and thin-film photovoltaic technology — actually helped Team Germany win the 2009 U.S. Department of Energy's Solar Decathlon.

Team Germany's Cube House was one of the most technologically advanced among the 20 clean energy prototype designs on the National Mall. Every exposed face of the building was covered with power-generating panels.

On the roof : a 11.1-kW photovoltaic (PV) system of 40 monocrystalline silicon panels. On the sides: 250 thin-film panels that look like glossy clapboards. The thin films used copper-indium-gallium-diselenide layers, or CIGS.

The combination system was expected to produce 200 percent of the energy needed by the house. The thin film panels, while less efficient than conventional silicon, were projected to perform better in cloudy weather than silicon.

Team Germany got its proof on the competition's fifth day when skies turned slate gray and a cold rain splattered the solar village. By late afternoon, as federal commuters started streaming home and electricity demand throughout the city began climbing, the Team Germany house was producing 12.68 kW and consuming 12.33 kW, for a net export of .35 kW.

Team Illinois' house finished a close second, emphasizing energy efficiency over power production.

"Team Germany built a gingerbread house packed with solar panels," said Richard King, DOE Solar Decathlon director. "In the rain, the thin-film panels were making electricity. It made the difference."

NREL Manages the Decathlon

NREL has managed the biannual Solar Decathlon for DOE since the contest's inception eight years ago. Selection of the 20 university teams from North America and Europe begins two years before the actual competition.

The Laboratory sent 30 people to run the week-long contest on the National Mall, including installation of the homes with trucks and cranes, connecting them to Washington's municipal power grid, running the judged contests and monitoring the home's continual performance.

M II A II R II K Oct 27, 2009 1:50 PM

Solar superpower: Should Europe run on Sahara sun?

26 October 2009 by Fred Pearce

EVERY two weeks, the sun pours more energy onto the surface of our planet than we use from all sources in an entire year. It is an inexhaustible powerhouse that has remained largely untapped for human energy needs. That may soon change in a big way. If a consortium of German companies has its way, construction of the biggest solar project ever devised could soon begin in the Sahara desert. When completed, it would harvest energy from the sun shining over Africa and transform it into clean, green electricity for delivery to European homes and businesses.

Prospects for the project, called Desertec, have blossomed over the past year, and this month 20 major German corporations are expected to announce the formation of a consortium that will provide the €400 billion needed to build a raft of solar thermal power plants in north Africa. They include energy utilities giants E.ON and RWE, the engineering firm Siemens, the finance house Deutsche Bank and the insurance company Munich Re.

The current plan, outlined by the German Aerospace Centre (DLR) in a report to the federal government, envisages that the project will meet 15 per cent of Europe's electricity needs by 2050, with a peak output of 100 gigawatts - roughly equivalent to 100 coal-fired power stations. Preliminary designs in the German report show electricity reaching Europe via 20 high-voltage direct-current power lines, which will keep transmission losses below 10 per cent (New Scientist, 14 March, p 42). Trans-Mediterranean links will cross from Morocco to Spain across the Strait of Gibraltar; from Algeria to France via the Balearic islands; from Tunisia to Italy; from Libya to Greece; and from Egypt to Turkey via Cyprus.

Desertec would take its place in a wider European supergrid that conveys power generated from wind turbines in the North Sea, hydroelectric dams in Scandinavia, hot rocks in Iceland and biofuels in eastern Europe. Adding solar thermal capacity would help ensure a steady supply of green electricity.

But is this really the best use of such a colossal amount of money? Critics are lining up to point out the project's shortcomings. They say it could make Europe's energy supply a hostage to politically unstable countries; that Europe should not be exploiting Africa in this way; that it is a poor investment compared to covering Europe's roofs with photovoltaic (PV) solar panels; and that, while deserts have plenty of sun, they lack another less obvious but equally indispensable resource for a solar thermal power plant - water. Is Desertec really the model of future power generation, as its promoters would have us believe, or is it politically misconceived and a monumental waste of money?

Canned heat

Unlike PV panels, which convert sunlight directly into electricity, solar thermal electricity generation plants first trap solar energy in the form of heat, and use this heat to generate electricity just as a conventional power plant does. Solar thermal plants come in four main varieties. Three use mirrors that concentrate sunlight to heat oil, water or a molten salt, which is in turn used to generate steam that drives a turbine. The mirrors can take the form of parabolic troughs or an array of flat reflectors that redirect sunlight onto pipes suspended above them, heating the fluid that they contain. In the Mojave desert in California, an interlinked system of nine solar thermal plants which use trough mirrors has been generating up to 300 megawatts of electrical power for more than two decades.

Alternatively, a field of mirrors can focus sunlight onto a central ceramic heat absorber mounted on a tower. A prototype plant in Spain has 21,000 square metres of glass mirrors that heat the absorber to over 1000 °C and generate 1 megawatt. In the fourth type, a dish focuses heat on a Stirling engine which generates electricity by exploiting the expansion and contraction of a gas in a sealed piston chamber as it is heated and then allowed to cool (see diagram).

Solar thermal energy is now coming to the fore, as it proves itself to have several advantages over PV. Among these is its ability to produce electricity in power-station quantities, without the complex organisation that distributed generation entails. What's more, it can feed electricity into the grid at night as well as by day. This is done by storing the heated fluid in an insulated container and releasing it hours later when the energy is required. Storing energy from PV panels would require a new generation of high-capacity batteries - still a research project in its infancy for the scale needed. The clincher is cost. Building a power-station-scale solar thermal installation costs only a fraction of PV generators with the same output. As a result, an army of new solar thermal plants are being planned for the US, China, Australia and Israel.


TexasPlaya Oct 28, 2009 5:29 AM

^^^Seems like one of those ideas that's better on paper than in practice.

Personally, I think this idea would be suited for space, among other reasons, "the project will meet 15 per cent of Europe's electricity needs by 2050." If we would concentrate our energies (no pun intended) temporarily on space based solar power, we could solve a lot of energy woes without making the next energy leap (hydorgen, etc.). Average solar power per unit area (W/m^2) outside Earth's atmosphere during any given time period is about 136% that of Earth's surface during direct sunlight and is constant.

Although, going to the moon and mars would bring many benefits too.

M II A II R II K Oct 30, 2009 5:00 PM

China leads solar home revolution

Oct 29, 2009

By Ryan Rutkowski


China is the world's largest market for solar water heating (SWH). Since the 1990s, China has blossomed with an increase in annual production to 114.1 million square meters in 2007 from 0.5 million square meters in 1991, accounting for two thirds of global output. According to "The China Greentech Report 2009", the country has the world's largest installed base of solar water heaters, at over 125 million square meters, with one in 10 families such devices.

M II A II R II K Oct 31, 2009 3:34 PM

Europe's Saharan solar dream edges closer to reality
Europe's Saharan solar dream edges closer to reality

30 Oct 2009

James Murray


Ambitious plans to generate up to 15 per cent of Europe's electricity using giant solar farms in North Africa and the Middle East moved a step forward today, with the announcement that the coalition of firms behind the proposals has formally launched a new joint venture to manage the project.

The Desertec Group of 12 companies, including Deutsche Bank, E.ON, Munich Re, RWE, Siemens, as well as a raft of solar energy firms, today signed a deal to create Desertec Industrial Initiative (DII) GmbH, a limited liability company tasked with undertaking the groundwork for the project.

M II A II R II K Oct 31, 2009 3:40 PM

Prospects for solar: "It's like watching the Internet mature in 1995"
Prospects for solar: "It's like watching the Internet mature in 1995"

Oct 29, 2009

By George Musser


I may be one of the few people in my town to have solar power right now, but if the news I’m hearing from the Solar Power International trade show this week is right, a wave of installations is about to sweep the country. I wasn’t able to attend the show -- this blog is just a sideline for me and I couldn’t justify a whole trip -- but I had a chance to talk with two conference attendees, Mike Caliel, CEO of IES, a big national energy contractor that has gotten heavily involved in renewables, and Harry Fleming, CEO of Acro Energy Technologies, one of the biggest solar installers in California.

M II A II R II K Nov 3, 2009 3:35 PM

Sahara Sun 'to help power Europe'

2 November 2009


A sustainable energy initiative that will start with a huge solar project in the Sahara desert has been announced by a consortium of 12 European businesses.

The Desertec Industrial Initiative aims to supply Europe with 15% of its energy needs by 2050.

Krases Nov 5, 2009 7:18 AM

For those interested in proposed solar sites around Las Vegas. I would post the article, but it is just an interactive image and not much else.

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