How can I power a small heater

Being in New England during the winter, I would like to warm up the attic a bit. How do I go about finding the parts or a kit that I can make to power a small heater to run? My thoughts would be at the least just rin while there is solar power, the second would be maybe a battery backup. I would think I would need a power inverter since I don't think I would want a 12 volt heater since I wouldn't feel safe leaving that run while I am not at home.

Any links or ideas would be great.

Thank you in advance,
Don

Comments

  • BB.
    BB. Super Moderators, Administrators Posts: 33,590 admin
    Re: How can I power a small heater

    Your best bet would not to use Solar PV Panels to generate electricity for heating but to use thermal solar panels instead.

    Solar Photo Voltaic Panels cost about $5 per watt... Thermal Solar Panels cost about $0.50 per watt--so you can get 10x the amount of heat for the same price using thermal panels. Also, you would need about 1/5 the roof space for thermal collectors as equivalent Solar PV panels. People also can build their own solar thermal collectors too pretty successfully.

    There are water, antifreeze, and air based units for thermal collectors. The liquid based can use electric water heaters to store the heat (for domestic hot water, or stored heat release). The hot air types can be vented directly to the room to heat--some folks use an insulated room of water barrels or rocks to store heat for later use (used a bit in the southwest, have not heard of people using in New England).

    Using batteries to store electricity for heating is also not very cost efficient (your average "car sized" storage battery would reliably only run your 1,500 watt electric heater for 20 minutes--and at that high discharge rate for one battery, it probably only last a few months before needing replacement)...

    Of course, throwing money can "solve" any problem... But take a look at thermal collectors first--and remember, you ideally need good solid sun from about 9-3pm on a sort-of south facing collector. Other orientations will work, but you would need larger collectors to collect the same energy. And, if you are in a coastal region with lots of clouds/fog/winter shading from trees/buildings/mountains, you will collect much less energy.

    Comments? Questions?

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • BB.
    BB. Super Moderators, Administrators Posts: 33,590 admin
    Re: How can I power a small heater

    By the way, I also want to add that your first dollars should go towards insulation (wall, double pane vinyl or wood windows, etc.) and conservation... You probably already have this in New England--but here in California, very few older homes have much insulation except for a little bit sometimes blown into the attic.

    -Bill

    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • System2
    System2 Posts: 6,290 admin
    Re: How can I power a small heater

    Great, I will look into that. Thanks for the input.
    DOn
  • BB.
    BB. Super Moderators, Administrators Posts: 33,590 admin
    Re: How can I power a small heater

    Don,

    Here is one thread where I was asking/looking into solar hot water (I have yet to do that--but that is because I would probably have to hang the panels on the side of my house to get good sun--used up my good roof space for Solar Electric):

    http://www.wind-sun.com/smf/index.php?topic=1515.0

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • BB.
    BB. Super Moderators, Administrators Posts: 33,590 admin
    Re: How can I power a small heater

    I should also add, for room heating, home built can also be a very good way to go...

    I can't find the link now, but one guy did a very neat solution for his barn/shop for warming his shop during the day... Basically (from memory, use the solar rules below to confirm the numbers):

    1. 8' Insulated wall, south facing
    2. Build a, roughly 3"-4" false wall with a piece of black metal--corrugated tin?-- at 1.5-2"
    3. Cover outside with clear corrugated fiberglass and seal.
    4. Cut 5"x15" "duct holes" with screens in top/bottom of wall/solar heater to allow circulating air from room to panel to room.
    5. On inside upper openings, staple top of light plastic on inside wall over screen to make a "check valve".

    Here is a link to somebody who built a simple solar collector for a mobile home wall (interestingly, I could not find any comments on how well it worked:

    http://www.mobilehomerepair.com/article17solar.htm
    http://www.mobilehomerepair.com/solarrules.htm (nice set of design rules for solar heater)

    Here looks like a good reference link for solar:

    http://www.nrel.gov/learning/fr_passive_solar_heating.html

    And here is a nice article on solar heat and heat storage (rock, water, phase change) from Purdue University:

    http://www.ces.purdue.edu/extmedia/AE/AE-89.html

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • SolarJohn
    SolarJohn Solar Expert Posts: 202 ✭✭
    Re: How can I power a small heater

    Don,

    I agree with most of the advice you've recieved, and want to add this:

    You might consider a pellet, or corn-burning stove for supplemental heat.  I installed a corn-burner in my home to serve as a backup heat source, and to cut down on my heating bills during the coldest months of the year.  I also have a small solar photovoltaic system and a small generator to keep things running in the event of a power failure. 

    Due to an ice storm, the grid-supplied electricity has been out at my home for more than six days now, and the outside temperatures have dropped into single digits.  I am using electricity from my solar PV system (part of the time), and my generator to keep the blowers running on my corn-burning stove.  I'm maintaining about 68 to 72 degrees inside. 

    I chose a stove that is not highly automated in order to keep electricity consumption low.  With this spell of very cold weather I've been burning about 75 pounds of corn a day at a cost of about $6.00.  I'm burning about 2 gallons of gas a day in my generator, but the solar power is free!  I'm planning to enlarge my PV system soon so that I can further reduce the need for the generator.

    For more info, visit the following:

    www.iburncorn.com
    http://solarjohn.blogspot.com

    John
  • niel
    niel Solar Expert Posts: 10,300 ✭✭✭✭
    Re: How can I power a small heater

    don,
    i am trying to understand this better so i have to ask if this is living space or not, as most attics are not living space? some are later converted to living space. heat naturally rises unless something impedes it like the insulation between the living space and the attic. if it is normal living space something is very amiss that it should need warmed up a tad so it may be underinsulated as had been mentioned, but i would suspect air leaks and/or a heating system design flaw. a design flaw could be an undersized radiator or the lack of a cold air return for forced air systems. it could even be that there is a blockage of the radiator or vent, though small, you wouldn't visually notice except to physically feel colder. it may be advantaious for you to seek the evaluation and advice of a qualified and reputable hvac outfit before committing to a solar installation.
    ammending here that by solar installation i meant it for thermal and not photovoltaic.
  • System2
    System2 Posts: 6,290 admin
    Re: How can I power a small heater

    taking another slant: they sell 12v pellet stoves at some places. still, id be willing to bet (alot) that thermal ould be cheaper, and better way to go all around.
    yeas i dont ge tthe heating the attic thing either unless its furnished with no heat, and that detail was left out
  • mike95490
    mike95490 Solar Expert Posts: 9,583 ✭✭✭✭✭
    Re: How can I power a small heater

    Propane

    (sorry, trying to heat with solar electric is just as silly, unless you are using the solar to run a fan, then it's an air stirrer, not a heater)
    Powerfab top of pole PV mount | Listeroid 6/1 w/st5 gen head | XW6048 inverter/chgr | Iota 48V/15A charger | Morningstar 60A MPPT | 48V, 800A NiFe Battery (in series)| 15, Evergreen 205w "12V" PV array on pole | Midnight ePanel | Grundfos 10 SO5-9 with 3 wire Franklin Electric motor (1/2hp 240V 1ph ) on a timer for 3 hr noontime run - Runs off PV ||
    || Midnight Classic 200 | 10, Evergreen 200w in a 160VOC array ||
    || VEC1093 12V Charger | Maha C401 aa/aaa Charger | SureSine | Sunsaver MPPT 15A

    solar: http://tinyurl.com/LMR-Solar
    gen: http://tinyurl.com/LMR-Lister ,

  • System2
    System2 Posts: 6,290 admin
    Re: How can I power a small heater

    Yeah, solar produced electricity and electric heat are a no go. Don't even think of them in the same thought, unless you have unlimited finances, like NASA. And no, I'm not joking.
    Read up on and study the whole solar electric thing and the "Solar way of life".
    For most, like myself, going Solar is a whole different way of life, where the #1 rule tends to be: "Conserve;conserve;conserve."
    Electric heat is possibly the single worst use one can put precious solar electricity to.
    This post is NOT to insult you or put you down in any way - - we all have to start somewhere, rather it's an attempt to help get you on the right track with all that solar CAN do for you.
    Direct solar heating would be the way to go. It DOES work and works well.
    Best of luck.
    Wayne