Solar

[Jcb]

Can anyone give any ideas on Pv solar to heat element,to heat small buffer tank,to heat small quantity of rads in a log cabin????

 

[FishScreener]

Huh? I understand the PV solar and heating element. Not sure where your headed from there.

 

[Jcb]

Huh? I understand the PV solar and heating element. Not sure where your headed from there.

Just looking for some idea to keep a little heat in log cabin,in winter months while we’re not in it.????

 

[FishScreener]

Just hook a solar panel to an electric heater. Make sure the max output from the solar panel is less than the max wattage of the heater. Do not add: controllers, or batteries, and you may not want the thermostat.

If you try to go from solar photovoltaic, to a water heater, to a circulating pump, to radiators, you’ve added a lot of complexity, and things that can break.

Keep it simple, the photovoltaic direct wired to the heaters is as simple as it gets.

 

[Diehard]

I'm not very familiar with PV solar so must ask, is this to say you can go directly from a panel to a DC powered electric heater? And as it sounds, more than one heater is required. Does that mean each panel to each heater?

 

[FishScreener]

Yes you can wire direct from a panel, or group of panels to get the right voltage, to a resistive heater. Depends on how you set it up on whether you need multiple arrays.

 

[chiraldude]

You need to come up with a minimum wattage needed to for your purpose. Then, you need to calculate the number of solar panels needed to get at least that much power. Take in to consideration number of available sun hours given typical cloud cover, trees, terrain, and latitude. (where are you located BTW?)
Then you need to figure out how to power a heater. Maybe a 12 volt heater but if you are going to wire it directly to the panels, it should be able to work with convection since a blower motor may or may not work with the fluctuating voltage.
Next level of complexity would be to get some deep cycle batteries and a charging regulator to store the electricity. Then you could have a thermostat that only turns on the heaters when needed. Charge batteries during the day, run heater at night, repeat....

 

[Jcb]

[okQUOTE="FishScreener, post: 103464, member: 16377"]Yes you can wire direct from a panel, or group of panels to get the right voltage, to a resistive heater. Depends on how you set it up on whether you need multiple arrays.[/QUOTE]

 

[Jcb]

Ok,thanks lads. Sorry I didn’t get back to you before now.yea I think I will go with panels direct to heater.Just not sure where to buy panels?

 

[WyrTwister]

Do you have south facing windows in the cabin ? If so , open up the shades / blinds / curtains . Solar heat . A non cost starting point .

https://www.harborfreight.com/100-watt-solar-panel-kit-63585.html

Very rough guess for 100 watts . Typical plug in 120 VAC electric heater = 1500 watts . Do the math .

Did not find the dimensions of the HF model . You can probably find better pricing on , say 10 - 15 of them .

If you have comercial AC power or propane heat , the solar looks less practical .

Wyr
God bless

 

[Mikey]

Using the sun to heat water directly is the most efficient - far superior to electric-based. When I lived in Florida, a hurricane passed through and wiped out the grid for close to two weeks. I had a small generator to run the well pump, but cold showers got old pretty quick. I looped a 100' black garden hose on the roof and plumbed it in in series with the water supply to the water heater - Viola! hot showers. If you Google "solar hot water black pipe" you'll find a ton of videos, articles, and websites describing simple ways to heat water.

 

[WyrTwister]

Very good plan . The hot water tank is somewhat insulated , so it can store some hot water while the sun is down or it is overcast . Be sure the T&P valve is working properly as there is no control as to the temperature of the " solar heated " water .

I think a convection flow ( no pump required ) solar heating system can be installed , be sure to use " antifreeze : instead of tap water .

Wyr
God bless

 

[FishScreener]

Using the sun to heat water directly is the most efficient - far superior to electric-based. When I lived in Florida, a hurricane passed through and wiped out the grid for close to two weeks. I had a small generator to run the well pump, but cold showers got old pretty quick. I looped a 100' black garden hose on the roof and plumbed it in in series with the water supply to the water heater - Viola! hot showers. If you Google "solar hot water black pipe" you'll find a ton of videos, articles, and websites describing simple ways to heat water.

The current cost of solar panels has dropped so far, and the efficiency is so high, that the direct solar water heaters now make little economic sense.

 

[Mikey]

The current cost of solar panels has dropped so far, and the efficiency is so high, that the direct solar water heaters now make little economic sense.

You're right; I'm still living in 1992. Good discussion of the topic at https://www.greenbuildingadvisor.com/article/solar-thermal-is-really-really-dead.

 

[WyrTwister]

I have a 200 amp 120/240 single phase service for our house . I could get by with a 60 amp service . Any Idea what a PV system for 60 amp service would coast ?

It would be necessary to take into consideration winter , overcast days and nights year around . Cost of batteries probably is a killer . and they have to be replaced periodically .

Wyr
God bless

 

[will-b]

Solar is the best