How to build a giant Solar Powered Oven

Does your house feell like a forced fan convection oven in summer?

Here’s how to build a highly efficient, giant solar powered oven.

Eight steps to making sure your oven gets as hot as possible in summer: powered by nothing other than the sun!

1. Erect a wooden frame about the size of an average house.

2. Build bricks around the outside of the frame. Bricks have a good thermal mass, which means that as the sun shines on them in the day, the bricks will store the heat and radiate it back into the oven long after the sun has gone down.

3. Fix a very low thermal mass material (like plasterboard) to the inside of the timber frame so that if any cool air gets in the oven (heaven forbid), the coolness won’t be stored in the inner walls.

4. Put lots of glass in the walls (avoid double glazing at all costs), especially the north facing one. Make sure these windows have minimal awnings.

5. Put black colorbond (ideally) or dark tiles on the top of the timber frame to maximize the heat absorbed by the ‘roof’ of the oven.

6. Add a fan that blows air down from the top of the oven. This way, as the hot air inside the oven rises, you can blow it back down to floor level to makes sure that anything on ground level gets suitably cooked through. To keep things simple, we’ll refer to this ventilation system as the ‘Ducted Air System’

7. If you are worried about cool air getting into the Ducted Air System, then simply add an insulated ceiling to create a roof space.  Ensure all the ducted air system’s pipes are kept inside this ferociously hot roofspace.  This will  minimize the chance of any air in the pipes actually getting cold.

8. If the meat in the oven needs a little more grilling, then add dozens of high powered halogen heaters liberally recessed into the ceiling. As well as producing enormous amounts of heat these little halogen bulbs will produce a small amount of light as an added bonus.

If your house was built like this and resembles an oven in summer,  the two most cost effective things you can probably do are:

a)   Fit mains or solar powered fans into the roof to remove the hot air from the roofspace. These will remove 7-10 times as much air as a passive ‘whirlybird’.

b)   Fit external awnings on all N, E and W facing windows.

If you do those and your cooling bills don’t halve, I’ll eat my cancer-council approved wide brimmed hat.

Do you trust your electricity supplier?

Before you invest in solar power, be sure that you know exactly what your local electricity company will pay you for any exported energy.  The good utilities will pay you the Feed In Tariff rate (if your state has one) PLUS the standard rate per kwh. The meanie ones will just pay you the FIT rate.

[Read more…]

New Ways To Finance Residential Solar Power Systems

How can Massachusetts residents afford solar power? The same way they get cable television. Though a long term lease on solar panels Massachusetts residents can now have solar panels atop their homes for a fraction of the cost of buying them outright.

Plus they begin to reap the savings on their electric bills immediately.
The state of Massachusetts wants to go green. Yet unlike California and Arizona the vast areas of sun drenched land is not available for giant solar parks. In an effort to convince residents to place solar panels on their rooftops Massachusetts has a state subsidy program, Commonwealth Solar.

[Read more…]

Don’t Get Fleeced by the Solar Cowboys

In the 1970’s some Australian companies started to research solar energy for use in the home but unfortunately the technology just wasn’t there.  At about the same time in China they were also researching solar energy and managed to produce some electricity producing solar panels.

A few Australian companies, believing in the future of solar energy, persisted in their research.  Eventually one of the most successful was bought out by the Chinese, and is now the biggest producer of panels in China! How short sighted could Australian investors be?

Now with the dramatically revived interest in solar energy and the Government’s renewable energy plan offering grants and rebates many companies are jumping on the bandwagon to proclaim loudly “Green is Good”. Some of these companies are fleecing customers for the best part of $20,000 for a 1kw Grid Tie system, simply because the poor consumer can’t find another solar installer who has the time or resources to give him a competive quote!

[Read more…]

Get the latest solar, battery and EV charger news straight to your inbox every Tuesday