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maybe somebody can tell me, i see wind turbines and solar panels advertised that put out 45watts and 350 watts and more. when they say they put out so many watts do they mean an hour or what? and how would you convert that to amps? would marine battery's work for storage.thanks for taking the time to read this.
They are rated the same way a generator is rated, so if a solar power panel was running at spec. (i.e. Direct sunlight) it would put out 350 watts. If it ran that way for an hour it would put out 350 watt/hours. Same goes for the wind generator. Wind is a little trickier since wind is rarely stable.
Typically, deep cycle batteries are the best for wind and pv systems - the kind that go in forklifts. To me marine just means, rated to be on a something in the water. My friend has 'marine' batteries that the insides are no different than a typical car battery. You have to make sure your battery bank and power generation capabilities match to be the most effective. Since any site I could point you to also sells things, I can't post it. Google is your friend here for sure.
I can't help much with what works in AK... But there are other people here than can.
You need to know what the conditions are for wind/solar are as well.
Some places in Alaska have winds almost 24/7 and others only a few days a month. I'd be lucky at my cabin in the dark of winter, if I got maybe three to five good hours of charging (on a clear day) when the sun creeped up over the mountains.
There used to be a site that had a lot of people that built their own homes (off-grid log homes and stick built) and powered them with solar/wind and some hydro - but it's been gone for over a year now.
The biggest issues is that in very rare cases one will work for your power needs - in other words, only solar or only wind, will suffice for your power needs.
Obviously solar will probably not work for you over the winter months.
But the very first thing you will need to do is figure out how much power you will need.
Marine batteries are a place to start - but they won't last as long and won't work as well as AGM or Gel batteries... but they are cheaper to replace if the need arises, but you will affect your systems overall performance by replacing only one battery no matter which way you choose to go.
And the rating is usually per hour and is usually a "max" rating - the manufacturer will have better information on how they figure the rating.
maybe somebody can tell me, i see wind turbines and solar panels advertised that put out 45watts and 350 watts and more. when they say they put out so many watts do they mean an hour or what? and how would you convert that to amps? would marine battery's work for storage.thanks for taking the time to read this.
When a generator or solar panel is rated at a certain wattage it means that is the maximum capability of the generator or solar panel at maximum efficiency. For example, a 45W solar panel will produce a maximum of 45W on a bright sunny summer day if the panel is at the appropriate angle.
Wind generators are no different. Most wind generators have automatic cut-offs when wind speeds reach about 45 mph to prevent damage, but they will also produce a small amount of electricity in winds as low as 5 to 10 mph. When the wind really blows you can probably expect maximum efficiency from the wind generator, but on most days it will be producing much less electricity than it is rated to produce.
Darkster is correct, deep-cycle batteries are what you want to use for storage. Both car and deep-cycle batteries are lead-acid batteries that use precisely the same chemical process. However, a car's battery is designed to provide a very large amount of current for a short period of time. Whereas, a deep-cycle battery is designed to provide a steady amount of current over a long period of time.
In addition to your batteries, you will need a DC/AC Inverter. It will allow you to draw current from your batteries to power household appliances.
Use these formulas for conversion:
Amps = Watts / Volts; or
Watts = Amps * Volts; or
Volts = Watts / Amps
For example, if you want to run a 13 Amp power-tool at 110 Volts, you will need 1,430 Watts of power. So the best thing to do is figure out what you want to run, how much total wattage it consumes, and buy a DC/AC Inverter that is rated slightly larger than your total usage.
To make life easier since it is tough (and sometimes inaccurate) to read the amps/watt requirements on electrical devices, either learn to use a standard electrical meter to measure the draw on the device or what I use is the kill-a-watt meter that I can direct plug in a 110V device and it tells me how many watts it pulls, how many watts it used over a period of time, and IIRC peak watts required (not 100% on that function, but something I had did that too).
Careful with power tools as electrical motors spike when the start, but then they use a less power to keep going. Perfect example is a pool or sprinkler pump. You need to have the surge capacity to start it, but not as much to run it.
We haven't even gotten into pure vs. modified sine wave inverters yet either -
To make life easier since it is tough (and sometimes inaccurate) to read the amps/watt requirements on electrical devices, either learn to use a standard electrical meter to measure the draw on the device or what I use is the kill-a-watt meter that I can direct plug in a 110V device and it tells me how many watts it pulls, how many watts it used over a period of time, and IIRC peak watts required (not 100% on that function, but something I had did that too).
Careful with power tools as electrical motors spike when the start, but then they use a less power to keep going. Perfect example is a pool or sprinkler pump. You need to have the surge capacity to start it, but not as much to run it.
We haven't even gotten into pure vs. modified sine wave inverters yet either -
With ANY off-grid setup, you would be a LOT better off finding appliances that are 12, 24, 36, 48 volt (according to whatever your system will be).
ANY inverter will "steal" a certain amount of power and affect the overall performance in the negative...
Buy a laptop and get a 12v charger - it runs on 12v anyway so why convert something you don't need to.
12v TV and Bluray players are out there, but not at places like BestBuy or any other retail store for the most part... special order maybe.
ANY item that has a "display", i.e. clock, "ready" or any other indication that it has power should be avoided like the plague - most will "steal" power even when they are off... even your TV when off steals a little bit of power - that's why it turns on so fast when you hit the power button, and remembers the time and channels... and yes even flat screens - mine has a little light showing it's "ready" so something is powering that light...
Stove, fridge, dryer should all be propane - Electric stove (220v) is not going to work anyway... unless you start out with a massive system. Same with the dryer... Fridge is OK as long as you buy the best insulated model you can find - keeps it from cycling all day just to keep it to temp.
All your lights should be DC (led or fluorescent) current incandescent bulbs are a no no - they aren't much more than little heaters anyway, and LED setups have progressed in leaps and bounds compared to when they first came out... and put closets, basements and garage on timers to keep them from being on for days because you "forgot"...
You have a lot of research to do if you truly plan on going off-grid... it's going to be nearly impossible for you to take "current" appliances you may own and go off-grid without spending a boat load of money to buy a big enough system to power it...
Any house is better off being designed from the get go to be off-grid... and it's easier than trying to take an existing house and going that way. Wiring is simple not there.
And as Dakster said, the ratings are usually a "max" rating... A 85w solar panel will produce 85w on the best of days and only if everything is optimal - from the panel being clean to the proper angle to the sun...
For your 12v and low power consumption needs - like water heaters, fridges, and washer/dryer's, look at RV appliances. You may also find some 12V lighting there as well. You could adapt some automotive LED lighting. If you can get propane or natural gas cheap enough use that when possible, also they make lights that run off of it too. Might be nice to have a couple of gas powered lights as a backup in case your batteries decide to give out on a windless, dark winter night. At least one 40lb propane bottle used solely for emergency heat/light might not be a bad idea. More if you could be stuck for days/weeks away from anyone. FWIW, RV fridges typically run on 12V/110V and propane, they auto switch depending on what is available. RV sized water pumps *should* be better more power efficient than 110V residential stuff too. The RV stuff can generally take a little more power fluctuations than traditional residential items, as the manufacturers know an RV's alternator isn't going to produce a steady 12V.
I agree on the laptop - you can always hook it up direct or with a docking station to a larger monitor and full size keyboard and mouse for the things the laptop is just too small for. Put the microwave (assuming you have a large enough system to run it), flat screen monitors, TV's, and anything else stays on to a power strip or switch that kills all the power.
And as DCbrewmeister said, LED and CFL have come along way in the past few years. 60 watts of light for 10w or less. I keep seeing prices falling and quality improvements, and I believe this will continue to do so. On a total off grid solution, I agree that incandescent/Halogen/Sodium Low-High Pressure Vapor lighting shouldn't be in your vocabulary.
BTW, any of you off grid folks heard of Bio-Lite? They make a small camp stove that burns about anything organic and it produces enough power to charge a cell phone. Supposedly they have a larger one coming out too, but I haven't checked on it in awhile.
For your 12v and low power consumption needs - like water heaters, fridges, and washer/dryer's, look at RV appliances. You may also find some 12V lighting there as well. You could adapt some automotive LED lighting. If you can get propane or natural gas cheap enough use that when possible, also they make lights that run off of it too. Might be nice to have a couple of gas powered lights as a backup in case your batteries decide to give out on a windless, dark winter night. At least one 40lb propane bottle used solely for emergency heat/light might not be a bad idea. More if you could be stuck for days/weeks away from anyone. FWIW, RV fridges typically run on 12V/110V and propane, they auto switch depending on what is available. RV sized water pumps *should* be better more power efficient than 110V residential stuff too. The RV stuff can generally take a little more power fluctuations than traditional residential items, as the manufacturers know an RV's alternator isn't going to produce a steady 12V.
I'd like to reply to using RV "stuff" for a home...
RV appliances are NOT cheap and are 100% meant for short term living...
Stoves are 22" wide... and are a foot off the floor... and generally only have one "big" burner 9500btu compared to a real gas stoves 15,000btu burners - the others two are generally 5 - 7,000 range. So longer burn times just to boil water.
Fridge is not meant to cool things down quickly like a real fridge will... they are only cooled with a thermal plate and if you put something warm in them, they can take hours to cool the inside back down... and they are horribly insulated... That's why it takes a full day to cool them before you go camping... It takes the better part of an entire day to make ice... I have a outdoor thermometer inside mine and if you put something warm (leftovers), the temp can go as high as 60 and generally doesn't come back down until nightfall. The kids constantly opening and closing the door will kill it in short order trying to keep up with demand.
A 12cu ft RV fridge is $3,000...
They also "automatically switch"... most default to 110, because in most RV parks you stay a day or two (most are up to a week) and electric power is included - so use all you want, it's "free" while your there.
Water heaters may not be that bad an idea, but on-demand hot water heaters would be a much better option for a home - RV's are 10 - 12 gal at most and don't "catch up" very well... you would spend more in propane keeping water warm than you would use with an on-demand unit - they are also horribly insulated.
Long term campers - "park models" have house style appliances...
If you buy a regular camper and live in it long term, you will void ALL warranties... you would have to admit you are but there is a reason and that reason is you will "overwork" all the appliances.
I'm living in mine - not to worry, warranties have long gone out of effect, and can tell you first hand RV appliances would be a huge mistake to build a house around... might be an idea for an off-grid cabin you visit throughout the year, but you have to consider the way RV appliances are mounted and vented... critter infiltration (vermin and insect) is a real concern.
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