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  1.  
    Dear Illustrious comrades,

    so we now live in our straw bale home and have a wood burning range which does all our cooking, heating and hot water in the winter. Come the summer our cooking options are much reduced in the house; no alternative to wood. Do use a rocket stove outside and probably will do a solar oven, but I would like to have an iven inside. Please would someone advise me about most energy efficient option for retro fitting into kitchen?
    I've looked at steam ovens briefly and wonder if they can easily be retrofitted. Don't have an obvious place/vent to outside, so the simpler the better. I dislike microwaves passionately.
    Do steam ovens need a place for heat/water to go? Do they make food kind of wet, steamed rather than roasted?
    I'm thinking a table top kind of style rather than big built in….
    Thank you!
    • CommentAuthortony
    • CommentTimeMay 12th 2015
     
    Solar oven!
  2.  
    I know, Tony…but I need a cooker inside as well. I'm thinking of something electrical….
    •  
      CommentAuthorSteamyTea
    • CommentTimeMay 12th 2015 edited
     
    Really down to physics.
    To cook a 4 oz potato takes the same amount of energy. It has the same specific heat capacity no matter what. You can cook it more efficiently though. So roasting it on your wood burning stove is not going to be the same as boiling it in a pot, or a microwave oven. They all loose different amounts of energy.

    Then there is the carbon foot print, here a solar powered oven is probably best (PV or ST), once the embodied energy of the panels and oven are paid off, the rest is carbon neutral.
    Anything that involves burning, either locally or at a distance, is not going to be carbon neutral.
    If you want to get an idea of how long it takes to pay back the embodied CO2 of a potatao by using a wood burner, work out the average ring count of what you are burning. So if the average is 10 rings, then it is at least 10 years to grow the similar amount of timber (contentious I know).
    • CommentAuthorGarethC
    • CommentTimeMay 12th 2015
     
    Aren't halogen ovens supposed to be good mainly due to extremely fast warming times?
    •  
      CommentAuthorSteamyTea
    • CommentTimeMay 12th 2015 edited
     
    Not sure, bet every type has some 'research' that makes the claim that they are more efficient.
    All about watts in and watts out.
    We could do a standard test.
    Set the oven at 180° (gas mark 4), put a litre of boiling water into a pre-heated dish, leave in oven for 30 minutes. Allow to cool and measure the evaporation losses.
    • CommentAuthorDarylP
    • CommentTimeMay 12th 2015
     
    I am not sure how scientific it is, but...
    ...we just have fitted a Neff oven.
    The o/s barely gets warm, the door is never hot, so I am guessing most of the energy input stays inside the oven?
    This would suggest it is quite efficient, and it certainly cooks a lot quicker than the old Hotpoint!

    Cheers
    :smile:
    • CommentAuthortony
    • CommentTimeMay 12th 2015
     
    Microwaves heat only the food, traditional ovens get hot so are less efficient.
    • CommentAuthorskyewright
    • CommentTimeMay 12th 2015
     
    Posted By: tonyMicrowaves heat only the food, traditional ovens get hot so are less efficient.

    It's over 2 year since we did away with even a hob. We just have 2 microwaves, a 1000W and a 700W (both "combinations, but hardly ever used as such). Two vegetarian adults. No kids. Suits us. No we don't live off ready meals. :wink:

    Oh, and a kettle, of course. :bigsmile:

    PS. There's a camping double burner and a gas bottle tucked away in case of emergencies, though the smaller of the 2 microwaves could be run off our generator.
    •  
      CommentAuthorcrosbie
    • CommentTimeMay 12th 2015
     
    Here's a nice counter top oven: http://www.amazon.co.uk/dp/B00VE1CJPI

    Here's a really efficient one: http://www.amazon.co.uk/dp/B00651T6AI (Russell Hobbs 18537 Halogen Oven )
  3.  
    Posted By: tonySolar oven!


    Would certainly go solar but using thermal oil. Unfortunately the ovens are still commercial quality used for patisserie baking as the end product is far better than similar ovens fired by gas or oil. You could also use heat recovery from your woodstove to heat the thermal oil so that you could use the oven all year round.
    • CommentAuthorgravelld
    • CommentTimeMay 12th 2015
     
    Posted By: GarethCAren't halogen ovens supposed to be good mainly due to extremely fast warming times?
    They are normally compared to conventional ovens, and the simple fact that they are much much smaller obviously helps. Not sure if they radiant heat is also a bigger factor than in a normal oven which is mostly convection?

    Slow cookers are great if you have PV - you don't need a very sunny day to get a free meal. Trouble is browning the meat (if you are eating meat) at the start ;) That said I've found you can actually sweat onions in our slow cooker given enough heat up time.
    •  
      CommentAuthordjh
    • CommentTimeMay 13th 2015
     
    Posted By: Carol hunterI've looked at steam ovens briefly and wonder if they can easily be retrofitted. Don't have an obvious place/vent to outside, so the simpler the better. I dislike microwaves passionately.
    Do steam ovens need a place for heat/water to go? Do they make food kind of wet, steamed rather than roasted?
    I'm thinking a table top kind of style rather than big built in….

    Miele do a nice counter top steam oven. Neff do some built-in ones. Panasonic do a nice counter top steam-microwave-grill-oven.

    The better steam ovens condense and catch the steam and/or recirculate it, so there's much less steam than when using a steamer on a hob. Most of these products have grill and/or dry oven capability as well as steaming, so they can cook things however you want them.

    As others have said, some halogen ovens are quite good if you don't need steam, and microwaves are probably the most energy efficient (I can't think of any reason they wouldn't be, but I have no evidence). I can't think of any reason to dislike microwave ovens, but there's no point arguing with passionate beliefs.

    There are various review sites for products. Which is a bit hit and miss because they only review a very few models. John Lewis is quite good to go and have a look.
    •  
      CommentAuthorSteamyTea
    • CommentTimeMay 13th 2015
     
    It is odd, in over 35 years in catering (on and off, my Mother owned a restaurant, I like to keep my hand in) I have never seen a steam oven, not once. I wonder why that is? When worked for a bakers, about 34 years ago, it was all electric oven, all the bakers I see down here seem to be the same.

    I don't think there is much difference between the energy usage of a microwave and an electric over, gas uses a bit more because it has to vent the combustion gases, electric fan ovens seem to use a little less, but that may be because you can cram more in them. I like electric fan ovens.
    Gas is my favourite oven type, seems to cook 'more gently', but the temperature spread inside them is greater (case of know your oven).

    If I was forced to have just one oven type for ever, it would be fan assisted electric, cheap to buy, consistent and easy to clean.
    One day I will find a decent grill, one day.
    •  
      CommentAuthordjh
    • CommentTimeMay 13th 2015 edited
     
    Posted By: SteamyTeaIt is odd, in over 35 years in catering ... I have never seen a steam oven, not once. I wonder why that is?

    Historically, they're fairly rare except in very specialist situations. Normally people have steamed things in water-filled steamers on a hob, or in closed dishes in an oven. I suspect that in most commercial kitchens that's still the case, because it's cost effective and the ventilation clears the steam. As the domestic market has developed, particularly in Asia, people are prepared to pay for more automation and less mess. So of the ones I mentioned Miele brought out their successful model several years ago, Panasonic is trying to build an all-singing-all-dancing oven and Neff is catching up as fast as it can.
  4.  
    So, to throw some different views in

    New top of the range Siemens oven does the lot - fan oven, grill, steam and microwave. Steam seems to be an increasing feature - have never used it but hear good things. I get the impression common in high end commercial kitchens.

    For me a fan oven works but must be "pyrolytic" - has a programme to get super hot and burn off all the dirt. Much better than using toxic oven cleaner. We only ran ours a couple of times a year and always in winter so all energy went to heat the house.

    Will likely try a steam oven this time - meant yo be great for defrosting and reheating without drying out as well as cooking. We're going to skip a microwave this time. I've no woo health fears about them, and I'm sure they're super efficient but they don't cook well. Reheating drys things out and is uneven, defrosting part cooks. Actually cooking pale wet and unappetising.
    •  
      CommentAuthorjoe90
    • CommentTimeMay 14th 2015
     
    I am wary about microwaves when I did my own research into cancer, I own and use one but only for warming stuff. I came across some information that indicated microwaves cook at above normal temperatures and so can change the food at a molecular level and the implications of this are not yet known.

    I have an electric fan oven and it's good, I also have a tiny cheap plug in worktop oven/grill and that's great to as you only heat a small space, got to be cheaper to run !!!
    • CommentAuthorCWatters
    • CommentTimeMay 14th 2015
     
    It's not limited to microwaves. My understanding is that "over heated" food (not just burnt or microwaved) has been implicated in some studies.
    • CommentAuthorEd Davies
    • CommentTimeMay 14th 2015
     
    Doesn't pretty much all cooking involve changing food at a “molecular level”?
    •  
      CommentAuthorSteamyTea
    • CommentTimeMay 14th 2015
     
    Anything that is cooked over 140°C (the Maillard Process) is.
    Boiling in water isn't, though some things change phase, like an egg. Liquid to solid. Which is strange when you think about it. It should get runnier as it gets hotter.
  5.  
    There's a study somewhere that proves just about anything you can think of causes cancer.
    • CommentAuthorEd Davies
    • CommentTimeMay 14th 2015 edited
     
    I could be wrong but this sounds awfully like changing food at a “molecular level”, what with breaking bonds between different parts of the protein, etc:

    https://en.wikipedia.org/wiki/Denaturation_%28biochemistry%29#How_denaturation_occurs_at_levels_of_protein_structure

    Whatever, my basic point is that saying that something is changed at a molecular level seems like pseudo-scientific way of making it seem more dramatic than it really is.
    •  
      CommentAuthorcrosbie
    • CommentTimeMay 14th 2015
     
    If you're interested in cooked food changing at molecular levels, you may be interested to know that in some industrial food processing factories in China they cook certain foods in a solution of Dihydrogen Monoxide - a chemical that can be lethal if the maximum recommended daily dose is exceeded. It may be carcinogenic too.

    http://www.dhmo.org/facts.html
    •  
      CommentAuthorSteamyTea
    • CommentTimeMay 14th 2015
     
    It is a slippery slope to a watery grave :wink:
    • CommentAuthorEd Davies
    • CommentTimeMay 14th 2015
     
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