Solar panels

hi,

Please any one can suggest me which is the best solar panel suits for a room having two lights, one air conditioner, one fridge and one LCD TV.

Just give me the name or link of the solar panel suits for this.

A start is here: http://tinyurl.com/2wt9xhk

But it would really help, if you tried to learn first what solar panels are, what amount of energy they can provide and how much energy those things you want to hook up to them consume.

Korman

one air conditioner

That’ll be the killer. Plan to spend a LOT of money to keep the juice up to an air conditioner.

Don’t forget batteries, regulators and inverters as well. Plan to spend maybe $20-30k with an AC, $3-4k without.


Rob

EDIT: Forgot batteries.

The air conditioner and fridge won't give off any light at all, except when the fridge is open.

Oh I don't know, the AC probably has a pilot light. Hack that to drive a transistor and a relay then hang a 500w halogen work light off that and shine it onto the panel. Same with the fridge but that needs 1000w to compensate for the door being open all the time.

As an added bonus we will get to find out if the light really does go off when you close the door.


Rob

best solar panel suits for a room

Where is this room located? is it a house in the outback or ...? orientation?

Besides generating enough power for the devices mentioned you could also consider insulation and paint walls / roof white to prevent heat from coming in. Place trees to provide shadow. etc. Consider using the exhaust heat of the AC and fridge to heat water (for shower / dishes etc)

Be aware that you need quite some space for the panels, not in the shadow of trees (etc) as this influences the output dramatically. Putting the Solar panels on the roof means quite some extra weight and question is if it can hold this extra weight. (+ the snow in the winter).

Solar panels don't work at night and at least your fridge should keep going, so think about a budget for a battery (six)pack with enough capacity. And as the sun doesn't shine every day the capacity shoulld at least be enough for 24 hours. A combination with wind-energy could provide a more stable system as the wind often blows on cloudy days.

Instead of "tracking the sun" solar panels that maximizes output (and costs) there exist panels (no link) with small "lenses" to concentrate light from any direction.

Saw this one recently as an alternative wind-energy harvester http://www.humdingerwind.com/.

Question: where does the Arduino comes in? Energy monitoring and management or sun-tracking or ...?

Don't forget batteries, regulators and inverters as well. Plan to spend maybe $20-30k with an AC, $3-4k without.

Also, don't forget a place to house the batteries, regulators, inverters, etc - as well as the costs for the electrician if you do a grid tie, plus yearly maintenance costs for the batteries...

...based on everything I have read and seen, it takes a fair amount of work (and money) to be off-the-grid...

;D

Im in the process of taking my shed of the grid ;)

I've lived off-grid for about 10 years now with systems from a 2-panel 2-battery setup in my 4x4 to a system large enough to build my RV with, including welding and large power tools.

It does take work and money, no way around that, but it's good to be independant. However the orther side of the coin is that when something breaks it's you problem, you can't just ring the electricity supplier and tell them to get it fixed.

BTW, the 2-panel 2-battery setup I had would be suitable for seenu@SDC as long as he has a DC fridge and no A/C. A small 300w inverter will handle many appliances, the TV and a laptop if needed.

Oh, and don't forget a small generator for cloudy days.


Rob

To get an idea of the possibility of the scale of your project, look up the subject on YouTube. "off grid" also works for good results on solar systems.

can any one tell me the approximate solar panel capacity(watts and cost) required to run the following things per hour.

Two RGB LED lights (To light a 150sqft room) One air conditioner ( " ) One fridge (General usage) One LCD TV (21 inches) .

And also tell me what is the individual power consumption per hour of the above.

Do you already own these items? If so look on the back for the watts used and X that by the hours you think it will be running for each day.

If you haven't got them you're pretty much asking for how long a piece of string is.

My 240ltr fridge uses 2A x 24v (48watts) and is probably running most of the day. But that's been converted to DC and had the auto defrost removed. If you're talking about a standard domestic 240/120v fridge maybe triple that plus add losses through tthe inverter.

LED lights, not much, let's say 30W.

My LCD TV is a 14" and uses 45W.

A/C, at least 2000W or more.

So let's have a guess for your (unspecified) devices and times.

lights 30W x 4 hours = 120W fridge 150W x 20hrs = 3000W TV 80W x 4 hrs = 320W A/C 2000W x 8hrs = 16000W

That's about 20,000W a day.

On average you allow for 5 hours of sunlight a day (where are you?, that makes a big difference), you need to generate 20000W of power during that 5 hours or 4000W instantaneous. So that will mean about 4000W of solar panels, about 33 120W panels or around $33000. Where will you put them?

Say $500 for a solar regulator.

Batteries, no real way of knowing because it depends when you run things like the A/C, during the day not so bad, at night you need a lot of batteries. Maybe 10 or 20 batteries, $4000 to $8000.

2000W Inverter, maybe $2000-3000.

Housing, wiring, tradesman costs, say $1000-2000.

Decent generator, $1000-$4000.

So maybe $35,000 to $40,000 but to be honest all the above is based on so much conjecture as to be fairly useless. I have a mate living in a small house and he spent $50,000 so I know the above is the right order of magnitude.

Bottom line, plan to spend a lot.

Ditch the A/C and buy an efficient fridge (not a domestic one) and it's a whole different ball game.


Rob

A little off-topic…

The reason the price is so high overall is because, as requested, we are all talking about solar panel only. If you have access to other energy forms such as wind or water… then for approx $30K USD (installed) the average home can leave the grid. Over the last couple of years we just hit the ‘tipping point’ for ?alternative? energy, being that the cost of leaving the grid is the same as the cost of staying on the grid over the expected lifetime of the equipment plus maintenance.

Unless you have an abundance of ?alternative? energy or you want to play with a reactor based steam turbine along with the cooling towers, then it’s best to equally try to reduce usage along side using ?alternative? energy collection methods… Live in a zone where the average temperature is generally stable and close to the temp you prefer, move underground where the temp is generally stable all year around, limit activities that require light to day time, etc,…

On Topic…

The “best” solar panels are whichever are the highest efficiency that you can afford. Remember, you can save 5%+ in efficiency every time you eliminate a conversion from AC to DC or DC to AC.

it's best to equally try to reduce usage

Precisely, hence my constant yammering about ditching the A/C.

The OP seems to have disappeared without telling us any more, like where he lives, he may be in the Sahara for all we know. But I spend much of my time in outback Australia in temps up to 40C and never feel the need for an A/C although I don't argue that it would be really nice a lot of the time.


Rob

Yeah Rob, not to diminish the heat you feel there but you need water versus cooling if that's the arid part of Australia, if the OP lives in a hot AND humid area then they may ?need? the cooling system more. As you said, they didn't provide sufficient details to discuss their use of the power.

I would actually mix the A/C and Fridge into a single unit if I had no choice but to keep both functions and really limit the size of either. Of course, as you may know, a fridge isn't really required for many of us, it's more of a city folk appliance for keeping goods fresh as long as possible so you can leave your domicile less often and purchase in bulk. Many people going 'off the grid' don't stockpile food that goes bad so quickly.

So the conversation has went a little deeper than putting a single living space on solar power...

hot AND humid area then they may ?need? the cooling system more

Yes good point, when it gets too humid we head south. Humidity is a real pain.

leave your domicile less often and purchase in bulk. Many people going 'off the grid' don't stockpile food that goes bad so quickly.

We try to buy every 2-3 months and can easily live that long without hitting the shops although the choices are a bit slim after a while and there's obviously no fresh stuff left.

a fridge isn't really required

I'll have to disagree most strongly there, where would I put my beer? :)


Rob

sounds neat :)

Of course, as you may know, a fridge isn’t really required for many of us, it’s more of a city folk appliance for keeping goods fresh as long as possible so you can leave your domicile less often and purchase in bulk. Many people going ‘off the grid’ don’t stockpile food that goes bad so quickly.

If I was really going off the grid, and lived out in the boonies here in Arizona, I would try to use “dark/night sky” radiation for my refrigeration needs. It would at least be worth experimenting with.

For cooling, I would investigate a couple of possibilities, if A/C wasn’t in the budget: Evaporative cooling via a “waterfall” cooling tower, and/or underground buried piping. Both methods though are low energy use (basically a pump and/or fan) compared to A/C, and both work well in arid environments.

They both do have the drawback that you would need to carefully monitor them and not leave standing water (less an issue in the underground pipe system), so as not to have a legionnaires disease breeding ground. They also take up a lot of room, but if you are living in the boonies, you generally will have some land to spare, so its not a big issue, other than the time to build and install (and the equipment needed).

Running water down hessian walls is good. I had a mate years ago on an outback property, they had a cool room with hessian walls soaked by a tank on top and some drip mechanism that I can't remember now. It worked pretty well but was bore water so stunk like rotten eggs, after a while you don't notice though.

Another thing to do (as you mentioned) is use the "deep earth" temp that never really varies and rig up a heat exchanger. Just bury X metres of pipe in the ground and circulate between that and a "radiator" in the house. Because it's a closed system there's very little energy used to move the water and you don't have the legionnaires problem.

In Aus we have towns where half of the people live underground like something from star wars. You buy your land and dig into the side of a hill to make a house.

This is a shot of the hill above a motel, the pipes are ventilation for the guest rooms.

On a similar note, check out this hot water system

A role of poly pipe layed out in the sun. It works a treat and I actually recommended this to an Aid agency working in Africa a few years ago as a cheap low-tech method of getting hot water. Apparently it did the job.


Rob

Another thing to do (as you mentioned) is use the "deep earth" temp that never really varies and rig up a heat exchanger. Just bury X metres of pipe in the ground and circulate between that and a "radiator" in the house. Because it's a closed system there's very little energy used to move the water and you don't have the legionnaires problem.

forgive me for being uninformed, but what is the legionnaires problem?