DIY solar oven ?

[russ]

The OP is an avid user of solar ovens. Who knows, a 1% type may come along and want to try it.

[Sunny Solar]

What do you think is the best choice : DIY solar oven or buy one to professionnals ?That was the original question. There was more than a fair chance the person lives in a place where it does not snow all year or at Mt Everest heights or live where there is no land at the north pole.He most likely lives where there is enough sunshine to make its use viable.If he lived in the middle of Alaska or Greenland he would have been aware that there was inadequate sunshine ,and would not be asking if better to buy or DIY.
All you gave was negativity,nothing useful,nothing that would really help him make a decission .
I tried to give him my experiences of making one to show you dont really need to buy one and they can be made simply and cheaply with limited carpentry skills.I gave in the hope he would find that information useful and then may decide to "give it a go" Who knows he may have actually enjoyed making something useful and liked to use it.

[russ]

Try using one in the Alaskan interior in the winterAnd that would be about 1/2 a % of the worlds land mass.

The same would go for the rest of the world toward the North pole - same for the South. Not a lot of population but a lot of land.

[Sunny Solar]

Try using one in the Alaskan interior in the winterAnd that would be about 1/2 a % of the worlds land mass.

[russ]

Russ I have filled up 2 passports in the last ten years and quite a few in the previous 30 yrs...I think it is safe to say I have seen just about every squaller and slum area in most countries.. And if there are some I have missed its not important I have seen enough.
Its not expensive to make bricks that are adequate to keep an oven hot for hours.
its useless trying to explain this to you as you obviously have never used a good solar oven . but it may inspire others to give it a try as they have nothing to lose as it costs very little to build one. and they may actually have fun building and using one.

So you have traveled - next time look around while doing so - maybe that would help. I spent 30 years working outside the US and then retired to my my present location.

[Wy_White_Wolf]

[COLOR="#0000FF"]...What locations cant they be used? ....

Try using one in the Alaskan interior in the winter. They don't work well when you get in the higher latitudes in winter months.

I do have an SOS Sport that is used when we are at the ranch. Being off grid and hot in the summer it makes sense. I can't see firing up the propane stove to cook unless absolutely needed and with the fire danger this summer outdoor grills are pretty much banned unless setup on a concrete patio.

[russ]

You are quite correct that I have no desire to construct or use a solar oven.

[Sunny Solar]

Russ I have filled up 2 passports in the last ten years and quite a few in the previous 30 yrs...I think it is safe to say I have seen just about every squaller and slum area in most countries.. And if there are some I have missed its not important I have seen enough.
Its not expensive to make bricks that are adequate to keep an oven hot for hours.
its useless trying to explain this to you as you obviously have never used a good solar oven . but it may inspire others to give it a try as they have nothing to lose as it costs very little to build one. and they may actually have fun building and using one.

[russ]

1) They are good for limited hours of the day
2) Limited locations

What locations cant they be used? excluding high rise buildings
limited hours can be extended easily and at little cost by adding bricks or metal mass into the oven .
There have been made ones that have enough heat retaining mass to still be able to cook next morning.

Even if you do not count solar heated steam used for cooking (but I cant see that that is valid) there is still a huge number of direct solar cookers in use and the figures I gave is only some of the known numbers.

Country club stuff for sure - in the cities how are the poor going to manage this? Most slums in Bombay (now Mumbai due to politics) would have little exposure to the sun - I have been there. To add enough thermal mass to have heat the next morning you are talking about something far beyond the average peasant plus it would be a heat radiator during the day.

I wasn't going to comment on this any more but this is too good - go to the big cities around the world one time and learn what you are talking about rather than repeating what someone else has said.

Can the solar cookers be used? Yes but with rather limited application in most areas.

[Sunny Solar]

I was sus about solar cookers of any type until I actually built a parabolic reflector one from scratch . it took about a week. it was 4ft dia but it was hard to use as the focal point is only a 1/2 sq in. And one day it burnt a hole through my 1/4 in thick aluminium pot. It also needed to be adjusted to track the sun every 15 minutes.
Next one was oven 18in sq and aluminium foil reflectors. Box was not made to close enough tolerance and lost a lot of heat around the door and single pane glass. Only got to about 280 deg F .. tooooo sloooow.
My present one 30 in long and 18 in wide and 30in high mirror reflectors and 3in insulation between inner and outer box and double pane glass easily gets to over 400 deg F. and has ceramic floor tiles to retain heat for up to 2 hrs after sun down. Cooks as fast as gas oven or stove. And only needs sun adjusting about every 30 mins..

Build one it doesn't cost much and they are a lot of fun and a good talking piece for your visitors, as they save money on gas/electricity. We cook lunch and dinner most days with it.

[Sunny Solar]

1) They are good for limited hours of the day
2) Limited locations

What locations cant they be used? excluding high rise buildings
limited hours can be extended easily and at little cost by adding bricks or metal mass into the oven .
There have been made ones that have enough heat retaining mass to still be able to cook next morning.

Even if you do not count solar heated steam used for cooking (but I cant see that that is valid) there is still a huge number of direct solar cookers in use and the figures I gave is only some of the known numbers.

[russ]

Nothing wrong with the solar cookers - I am saying that

1) They are good for limited hours of the day
2) Limited locations

The numbers from do-gooder organizations are always suspect - country club numbers tend to include thoughts and wishes in the totals.

Locations using a solar concentrator to generate steam are a different animal and should not be included.

[green]

Do you have children? Or cook? Lol. I wouldn't stovetop cook from my livingroom. I love to cook btw I'm right in the kitchen lovin' it the whole time. I was refering to the oven. I was just saying when the oven is on I'm better able to monitor it than if it were outdoors. That's all.

Green

[Sunny Solar]

In 2009, China led the world with over 1.4 million solar thermal cookers.
India has developed solar thermal institutional systems which cook for
thousands of people.
The Clean Development
Mechanism (CDM) has
registered eight solar cooker
projects in China since 2009. A total of 207,000 parabolic
cookers have been
distributed, serving 848,000
people.
In 2005, GTZ, the German international assistance organization, did a
survey of household fuel consumption in the Tibet Autonomous Region,
(TAR). It found that families spent a large part of their income and time
obtaining fuel. At altitudes above 3700 meters, the daily fuel is one or two
bags of yak dung collected most days by the women in 3 to 9 hour forays
throughout the dry season. At lower altitudes, very poor women carried
wood from distant mountain valleys, walking up to 10 hours a day during
the collecting season. Others bought wood delivered by tractors.

GTZ reported that by 2007, 70,000 solar cookers were in use in the TAR.
By 2009, around 50,000 cast iron solar cookers were sold annually. 100
shops making concrete solar cookers were found in Qinhai Province and a
new factory was operating in Lhasa. Regular use of solar cookers reduced
consumption of wood and yak dung by half.
In India, CDM registered a Gold
Standard project in 2006.
Gadhia Solar company created
institutional kitchens with arrays
of large parabolic solar
concentrators to generate
steam. Such an installation at
Mt. Abu, Rajasthan, can produce
meals for 38,500 pilgrims per
day.

As you can see the use of solar cooking is not just a few do gooders from the country clubs giving a few hand outs to poor people ..

[Sunny Solar]

I still cant see how it can be anywhere near as dangerous as a gas or electric stove.. A gas or electric stove has either flames or a very red hot element that is easily touched on the top of the stove,saucepans containing boiling fluids can easily be pulled off the stove by the handles in a split second,far faster than you could get from living room to kitchen.And its not possible to be sitting watching the kitchen from living room every second.
Now a solar oven has the pots enclosed in the oven ,difficult to remove or be spilt by children. and the oven height would be abour 4ft above the ground. well above a small childs ability to remove the pot.
The outside of a solar oven is not above any other item left out in the sun. the only external part that gets hot is the glass cover and that is almost impossible to reach for a child because of their necessaty to be 2 ft high.. and are above the 4ft height of the oven above ground.

A reasonably well made oven using cheap materials well get to over 400deg F inside,as I already said, more than enough to cook anything.