Off grid idea...

As I understand Micro Hydro if you have the available resources is the way to go... But for most of us that is not an option. I have been researching going green and off grid for several years now and I have another possible idea that I have come up with that might actually be a option.

I came across a few sites and YouTube videos about a house running 100% off grid that uses solar and hydrogen. The solar powers a hydrogen diffusor and stores it in tanks to use as a reserve when the solar is not powerful enough.
There are several things wrong with this. First off the guys setup cost literally a small fortune. Most of his equipment was donated or sponsored as a proof of concept.

But it got me thinking...

Wind (or solar though I don’t like the costs and production of these systems) which would produce the energy you need for your house but as it is optimal it could also be powering an air compressor which would store large quantities of compressed air.

When the wind dies down it would switch over and used the storage of the compressed air along with the engineair system (http://www.engineair.com.au/) tied to an alternator. It’s basically a compressed air engine. Its still in development and when it’s completed it will cost around $500 per engine and I believe 2-6 of these depending on your needs would power your whole house from the compressed air reserves that are filled when the wind (or solar) is active.

I really want to have some feed back on this or any other ideas that would work out just as well if not better. I look forward to your responses.

I question the efficiency of compressing air and then using air motor, (air motors are pretty common in industrial applications). I would tend to think that storage in a battery is more efficient then the mechanical loss of compressing air and then the loss of converting it back into rotary energy to convert that back into electrical energy. I love using pneumatic tools in my machine shop and foundry, but the cost of compressed air is so much higher than other ways of powering tools. that and I am currently waiting for the day that I have to replace my compresser, it is leaking oil and probably the tank is rusting on the inside from all the condensation that drops out of the the air it compresses. Now if I had a steam outside and an overshot water wheel to run a compresser that would be a very different story.
kent

davidjackson wrote:

Its still in development and when it’s completed it will cost around $500 per engine ....

I have trouble with statements like that. If something is still under development, and has been for many years, how can a price tag be placed on future sales?  I've seen other claims for cars that will run on compressed air. When I search for current data on some of them I find they have faded away in some cases. Others are still there promising a lot but nothing yet delivered. Pardon me for being a skeptic. I would like to see some numbers; how much power is produced by such 'n' such amount of air.

I guess I'll stay tuned and keep waiting and watching while I enjoy the power my PV system supplies and my lead-acid batteries store.

The first thing I got was the 2 - 6 units required ... my first thought is that you are starting at the wrong end.... reduce how much you need first.... like never heat with power (even to cook) unless you are having to crowbar extra power from wind then the heat should be put to some use. Do less in the dark. Group tasks together to be done when non-stored power is available. Other people have covered most of the other points. I have always thought storing rain water as close to the eaves as possible and running a small generator while it was being transfered to a lower holding tank.... probably not enough to run a pump to replace the the water pressure used to generate said power. Storing the water up high might reduce the need for power to pump though.

off grid power points.
1) power is not required. (it is a recent innovation after all)
2) there are still a lot of places where it's use is better than the alternative.
3) before using power, try to find another way.
4) decide if it is worth while using power over an alternative for that task
      (or if you need that task, try doing without... you may find you don't need it)
5) remember that things that make sense on grid may not off grid (learn to conserve)
6) Sometimes powered and alternatives can both be used (lighting)
7) even if you have access to a stream it may not be enough
sun might not be enough
9) wind might not be enough
10) A mix might be needed.... but see number 1 and 3 first
11) for some things a generator makes the most sense (portability comes to mind)

Every situation is different, but always try doing without first.
For me number 2 is the big thing. I live on the grid right now, but am slowly trying to go off. I want to power things first that it doesn't make sense to do any other way. I'm starting with chilling....  first I need to see if there are better ways to store food so that the amount of power needed can be minimized.

Check this guy out. He invented the turbines for Royals Royce Engines.

edited by staff to fix broken youtube video

"@ Len "
I agree that I can defiantly learn to conserve a lot better and do with a lot less power hungry things that we have now. In fact I am trying to find some of the old school kitchen tools like hand cranked blenders and the like.

I don’t like the idea of having to Burn something though for heat or for cooking as that too releases harmful gasses into the atmosphere. But I understand that it at this point might be better then what I am doing now.

The goal we have though is to not just live green ourselves as the best we can but to come up with a way to create a eco village that has several modern things like computers etc but at the same time doing so in a reduced fashion and more conservative lifestyle. By doing this we can show the people who would not live the extreme eco village lifestyle that they too can reduce and conserve while keeping some of their comforts.

Thank you for your points though for sure as every little bit helps.

“@ Don Miller”
Hey Don. These engines are actually already being used currently in the Australian fruit market at this very time and so far have been a great addition to help reduce the pollution that is being released by the non-compressed air counterparts.

“@ Machinemaker”
I admit I am no engineer but from what I have watched, read and studied this engine actually is very efficient. I don’t know honestly though how its application could fit into what I am wanting to do with them but it is worth looking into.


Basically I think I am just going to have to find a lot of land with a very strong flowing water source and go with Micro Hydro but I just wanted to see what other options are out there.

Biodiesel, Natural Gas, Wood Burning all still have emissions. Solar Panels are not green at all in their construction even though they are in their application and their lifespan and limitations are not that appealing.
So far I think Micro Hydro is the best option so far. Just wish it wasn’t the only one.

I am a curious guy; where curious = inquisitive more than curious = odd, although I have been called odd at times.

I looked up the Melbourne Market that was mentioned. They have a website. No mention of EngineAir although there are references to requirements for propane powered vehicles on market premises. Also electric. No petrol allowed. I sent them an email inquiry to see how these things work for them. Just today, so no likelihood of a reply for a few days.
http://melbournemarkets.com.au/services_forklifts.asp

The other thing I am curious about is how much air is used to do a particular task. No info on that anywhere. Can I be faulted for wanting to know that basis piece of info?

I may have got myself confused looking through different webpages I found but I somehow I have it in my head that the air cylinder storage pressure is in the neighborhood of 300 BAR. There is a photo of a " state-of-the-art modern compressors up to 350 bar" on the EngineAir website. 1 BAR = atmospheric pressure at sea level, approx 14.5 PSI. So 100 BAR = 1450 PSI, 300 BAR = 4350 PSI. That much pressure requires one heck of a compressor, more than a typical garage compressor. I have serious doubts about driving one of those with a small windmill in the backyard.

davidjackson wrote:
"@ Len "
I agree that I can defiantly learn to conserve a lot better and do with a lot less power hungry things that we have now. In fact I am trying to find some of the old school kitchen tools like hand cranked blenders and the like.

Old school kitchen... I started baking bread with a bread machine... heat something up everyday... ok bread... decided to make 2 loaves at a time... used mixer with dough hooks and only heated oven up once for two loaves and loaves are better shape too. Today, I am baking 7 loaves, heat the oven once, more loaves in the oven means more steam in the oven, softer nicer bread. no mixer. Now if I can cook supper while the oven is still hot...

I don’t like the idea of having to Burn something though for heat or for cooking as that too releases harmful gasses into the atmosphere. But I understand that it at this point might be better then what I am doing now.

I have cooked almond flour bread with a solar oven, made rice with a solar cooker here in the Pacific North West, but the sun doesn't always shine.

A wood fired brick bake oven can use less resources than just about anything else if it is well built, and used continuously from hot to cool... sometimes two or three days. It is possible to make one heated by electric... 4kw for over an hour to get it to temp... for bread, not hot enough for pizza though. The rest of the house had better stop running while it heats if you are off grid.... if your inverter can deal with it or your stream is big enough. Or you can use one or two arm loads of wood. (and cook pizza)

Some times burning something is the best option. Something not very common in America that should (IMO) go with wood burning is coppicing.

The goal we have though is to not just live green ourselves as the best we can but to come up with a way to create a eco village that has several modern things like computers etc but at the same time doing so in a reduced fashion and more conservative lifestyle. By doing this we can show the people who would not live the extreme eco village lifestyle that they too can reduce and conserve while keeping some of their comforts.

Sounds good.... but..... Actually, I don't think I will say too much   I don't have a very good opinion of the human race in these areas, power is cheap compared to just about any off grid solution. (village size hydro may be different, but to the user it is just another kind of grid so why switch?) It takes no maintenance just flip a switch. Pretty good stuff from a consumers point of view. OTOH I am glad for your vision and I do hope some of your enthusiasm wears off on other people. I hope I can do things that will rub off on others too. I live in Courtenay BC on Vancouver Island.... We have a curious bunch of people here... old stick in the mud types and old left from the sixties hippies... oh, and the locals who grew up here. Not sure which I am The place is small enough that a bike is worth while transport and a lot of people do. Many people use wood for heat.... and I don't mean mass heaters either, they are the iron stinkers as free wood is easy to find or cheap to have delivered. I use hydro (real water hydro not coal) to heat, cook and everything else, but today fired up a drystack rocket heater core, and have bought some solar PVs to start getting less grid in my life. Besides the old hot water tank I am going to use as barrel for the rocket heater, I have another for a solar heating project... Yes even here with all the rain. I want to see how much I can do here in the city.

Basically I think I am just going to have to find a lot of land with a very strong flowing water source and go with Micro Hydro but I just wanted to see what other options are out there.

The only problem with micro hydro is the one I mentioned above, it doesn't work well with your goal of showing people they can go off grid and be green easy. It is just a mini-grid in most people's eyes. Wind mills and PVs are easy for people to see and imagine themselves owning. Most people are not going to think about the process that made them available. My opinion is that most people will change when they are forced to....

I have a report on the DiPietro air engine, straight from Angelo Di Pietro himself. It's the attached Excel spreadsheet.

Producing 3.8 HP it consumes 1250 standard liters of air per minute at an inlet pressure of 140 PSI. 1250 liters per minute is 44 cu ft per minute.

With 3.8 HP it is theoretically possible to turn that into (3.8 x 746) 2835 watts of electrical power with a dream world of 100% efficiency.

My big compressor puts out 22 standard cu ft per minute at 175 PSI. Two of them could supply sufficient air to run the DiPietro at the above rating. The tough part is compressing all that air into a cylinder small enough to be practical.

The compressor uses almost 25 amps at 240 VAC when running. That's 6000 watts. Times that by two compressors = 12000 watts.

Seems to me that the DiPietro engine is not very cost effective to run.  At least that is what it looks like to me. 

don miller; MountainDon wrote:
With 3.8 HP it is theoretically possible to turn that into (3.8 x 746) 2835 watts of electrical power with a dream world of 100% efficiency.
....
Times that by two compressors = 12000 watts.

So this engine (at best) is only half a solution, it sounds like using compressed air to store energy needs a very efficient compressor first. I would also suggest using this type of stored energy for turning things not to produce electric power.

Storing energy in kind for each application seems to be the most efficient way of doing things. Store heat to be used as heat, electricity to be used that way. No conversion is 100%.... no storage is lossless. Better yet is to use gathered energy as it is gathered (as in at the time it is gathered). Using storage that is more efficient at giving back what you store but lossy for short term storage and less lossy, but less efficient for longer term also makes sense. Then throw cost into the ring and use what you can afford.... I'm beginning to like wood heat as long term storage.... electric doesn't seem to have much of an equivalent besides a high altitude pond (aka reservoir)... still lossy, but (at least here) rain would help. Not sure if this is better than a battery, but at least it lets the animals drink and means I have backup water to drink.

I have been living off-grid for 12+ years and my advice is to just make the jump. I started with two 120 watt solar panels, a couple used forklift batteries, and a cheapo 1500 watt inverter. You can start off small and add capacity over time. I have a year-round creek that runs a ram pump during our growing season and plan to add micro hydro soon. I spent a lot of time looking for property and having usable hydro potential was a deciding factor. I also use compressed air for various pneumatic tools and plan to build a water powered air compressor and store the air in several decommissioned  500 gal. propane tanks which can be obtained for their scrap value. I do use propane for cooking and a gas generator for winter battery charging but plan to wean ourselves off those fossils with home grown methane and ethanol. Living off-grid has forced me to address conservation first and production second. It also made me start thinking and designing with permaculture principles before I ever knew what permaculture was.