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Author Topic: DIY Space Heater?  (Read 4799 times)

Offline JargonJam

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DIY Space Heater?
« on: 22/09/2011 05:22:32 »
I'm trying to make as many of the parts from scratch as possible, cost is not an issue but obviously the lower the cost the more accessible it would be for people to clone my end result. Parts that need to made from scratch:

1)Heating Element-Or any device that may be heated by sunlight or a small boost of electrical current but retains     heat really well. Think Kinetically for this one.

2)Intensifier- This device most likely a lens of some sort, should help as much of the solar waves that carry heat directly "fire" the element

3) Stabilizing Solution- This is what I plan on using to submerge the element in to increase the insulating effect and maintain temperature stability. (I wonder if sodium/lubricant would do the trick)

4) An air chamber- This part allows air to contact the heat and convective force should push it on out to keep a room comfortably warm.

I intend to try it out this winter and my home is in need of insulation so it would make a great benchmark when the temperatures hit the 20F's. Probably the coldest I've seen it get in South Georgia is closer to 5F.

So any suggestions? If it works out pretty well I'm happy to give credit to the participants and I plan on demonstrating it and showing people how to make them at DIY workshops and add a video to U-tube of course.
I'll be checking in here at least once a week to keep the ideas flowing. I'm hoping it catches on and helps a lot of people save money on their energy bill  ;D


 

Offline CliffordK

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DIY Space Heater?
« Reply #1 on: 23/09/2011 22:39:32 »
I'm not quite sure what your goal is.  There is a lot of info on the web about solar heaters.

Home insulation is important, and the more, the better.

A heat absorber might be a brick or concrete wall, and might be effective in the middle of the house.  Earth heating is also effective.  For example a house that has much of the house buried underground.  The temperature should tend towards the average annual temperature of the area.  South Georgia might be very comfortable year around for an "earth house".

I've seen several reports of soda can collectors that can be cheap to make, and surprisingly effective.

Another system I've seen discussed is a water heating system.  Use typical water (or glycol) solar panels on the roof which you route into a heat exchanger.  Then, either using an air heat exchanger, or perhaps a floor piping/heating system to warm the house.  It is easy to supplement with a more conventional heating system if needed.

I suppose one question that one should ask is what the winter sunlight is like in your area.  On the West Coast, we have many cloudy days in the winter rendering direct solar heating less effective.
 

Offline RD

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DIY Space Heater?
« Reply #2 on: 24/09/2011 04:42:35 »
Quote
Average U.S. Insolation Values*
City    Insolation Value
(kWh/m2 per day)
Anchorage, AK    3.02
Pensacola, FL    4.22
Chicago, IL    4.43
Atlanta, GA    4.74
Birmingham, AL    5.00
Miami, FL    5.26
San Antonio, TX    5.41
Las Vegas, NV    6.60

* Source: U.S. National Renewable Energy Laboratory
http://www.georgiapower.com/spotlightsolar/solar_potential.asp

You won't be able to extract all of this energy, (system cannot be 100% efficient).
A lens cannot make energy, nothing can ... http://en.wikipedia.org/wiki/First_law_of_thermodynamics
« Last Edit: 24/09/2011 05:09:18 by RD »
 

Offline CliffordK

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« Reply #3 on: 24/09/2011 16:17:49 »
City Data Dot Com has a number of great graphs about weather.

What I was referring to above.

In the Northwest, USA, we have a lot of cloudy days in the winter.

This is for Eugene Oregon.


Valdosta, Georgia, for example, shows a much different picture.


So, solar energy becomes far less effective in the west than in much of the rest of the country.  I assume that in Georgia, one should get significant solar energy about half the time year around. 
 

Offline JargonJam

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« Reply #4 on: 27/09/2011 00:51:39 »
Thanks for the replies everyone:

Thanks for the replies,

Clifford K.
~~~~~~~~~~~
I'm actually just trying to warm air and have it funneled into any room, your right about there being a good variety of things that can retain heat. I have indeed looked into the Aluminum can version of a heater I've thought about adding lenses over each can to increase their temperature. I'm not sure but I don't think refractive sunlight warms things as much as direct sunlight. I'm located just north of the florida border in GA and it can still be cloudy for a good month but spring sun visits early. The real trick is to build it out of the most efficient materials possible so that it outlasts in short periods of sunlight. As far as insulation, the house was originally constructed before there were any real building codes.....I think its been here since the mid 30's. So while the foundation is pretty darn sturdy the walls are not made to add insulation, only the later additions to the house have thick walls and insulation. Believe me, if I was given the go-ahead insulation would've been taken care of long ago, incidently that's why there's no central air unit as well but there are venting spaces and if I can constantly run hot air through them it will serve as a temperature stabilizer even if it doesn't completely warm the room that the vent will be directed to. The water heater idea comes rather close but I can't imagine that being too convenient when frost is an issue...and alcohols are a fire hazard so I think glycol is out of the question too... 


RD
~~

Good links, I think you misunderstood the use of the lens, but the concept is fairly simple when sunlight reaches a surface it is warming that surface evenly. However when focusing sunlight onto one point it warms that point faster because I'm condensing the same amount of sunlight for a whole surface onto one point. I believe your thinking more in terms of powering something with solar energy where my heater is simply kinetic there's no need to power it. It harvests solar energy not transforms it. I can see where my use of the word "element" might have thrown you off but Clifford K. has an idea where I'm going with this.
 

Offline CliffordK

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DIY Space Heater?
« Reply #5 on: 27/09/2011 04:56:01 »
Keep in mind that there are two types of focusing energy, either with a mirror, or with a lens.  Both of them will require a solar tracking system. 

A trough system with either a mirror or a lens only requires single axis solar tracking, whereas a 3-D parabolic system like a TV dish antenna would require two axis solar tracking.

A Fresnel lens, or the corresponding type of mirror can be made flat.  I believe there are large Fresnel lenses in projection TV's which you may find either on E-Bay, or perhaps find scrap projection TVs somewhere.

Keep in mind that the total amount of energy absorbed by focusing a 6'x6' parabolic mirror or lens, vs a 6'x6' flat panel would be the same, just the energy would be concentrated in a smaller location, thus more heat in a smaller area.  Depending on your application, this may or may not be necessary.

I picked up a few used trough parabolic solar water heater panels.  They have quite a simple design.  I haven't gotten them installed on anything yet, but I can take some photos if you need.  I was thinking about using them in a biodiesel system where a little more concentrated heat would be nice.

Most solar panels I've seen only have a single layer of glass or plastic for insulation on the sun side.  I'm not sure why double paned glass isn't used with solar panels more frequently.  If you are making something, used patio doors come in either single or double paned, are tempered, and are often very cheap.

Propylene glycol is used in conjunction with potable water systems because it is low toxicity, so if it leaks, the risk of ingestion is low.  Ethylene Glycol is of higher toxicity.  If you are using them for antifreeze, then one typically uses an aqueous solution which would minimize flammability.

A while a go I was looking at high temperature substances.  In some senses, Brake Fluid is like super-antifreeze.  However, it may be quite corrosive.  DOT-5 Brake Fluid has very low flammability, and is less corrosive than other types.  However, it is also quite expensive.

What is your house constructed of?  There are many methods of retrofitting insulation.  If it is a wood house, sometimes when people upgrade siding, they will add a layer of foam insulation under the siding.  It is also possible to put holes in the walls and fill with spray foam (usually done by a professional company).  If you have an attic or crawl space, it may be easy to retro-fit those areas.
 

Offline MissRepresent

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DIY Space Heater?
« Reply #6 on: 27/09/2011 18:00:20 »
WOW! i live in SG too! My hubz been talking about that stuff with me alot and it sounds like your on the same track.

Heating element, as you put it...
Thermal collector - we were thinking aluminum rail, black rubber hose or for potable water; pex pipe/tube or copper pipe/tube.

Heat Retaining fluids - Now were talking Fluid mechanics.
Motor oil is viscous at low temperatures but has high heat tolerances, higher viscosity should retain heat longer but also take longer to heat in the first place.
Mineral oil is much less viscous with a higher boiling point than water.
Mineral oil specs- newbielink:http://msds.farnam.com/m000712.htm [nonactive]


Intensifier- Solar/wind/city electric heating element, to heat by battery when sun is lost.
Trough for directing sun to normally unexposed areas of the thermal collector.
Solar powered sun tracking mechanism for troughs.

Stabilizing Solution- Insulated box and tubing. Maybe fire retardant?

An air chamber- Central ac duct work perhaps running from the radiator.

Fire based alternate to heat the radiating fluid in times of extended darkness and windless days.

With the radiator version you may have cheap/free hot water and hot air!
 

Offline JargonJam

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DIY Space Heater?
« Reply #7 on: 14/10/2011 02:47:03 »
I know! it's been forever since I last posted in here....sorry guys, its been hectic but fear not this little post was not forgotten...I've been doing a lot of experimenting with gases and I've discovered that convection is KEY! to making everything come together. I've had some pretty wild ideas come to light and figured that friction is perhaps a better option than sunlight when it comes to creating a heat generator... I shall be putting a design together here pretty shortly and later post my results within the next 2 months here (mainly waiting for temperatures to start dropping) and all of the information here has come in real handy TOO not to mention some inspiration from my Earth Science class as well so keep me posted!  :D
« Last Edit: 14/10/2011 02:50:03 by JargonJam »
 

Offline JargonJam

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DIY Space Heater?
« Reply #8 on: 28/10/2011 04:10:22 »
getting the walls to absorb heat would be a good option. The thing is I'm trying to make something that's adaptable to most standing structures and requires very little to install. The design should be practical enough that any structure from mobile home, to typical household, to a factory or plant should be able to fit it with minimal tooling and labor even a tent would be suitable enough. It's a good challenge and it may just change the way people currently think of heating...


yes i realize the previous post was just spam, but i think it needed to be said  [:I]
« Last Edit: 28/10/2011 04:14:49 by JargonJam »
 

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