Micro CoGen.

Well I'm going to venture into the world of engine driven ac systems. I've been collecting parts and I still have a few more to go. My plan is to build a tri-gen system for my house/garage. So far I have a z482 Kubota an ac compressor from an 06 mazda3(it was free)also  an old 3ton condenser coil with fan. I think I'm going to buy a brazed plate heat exchanger for the evap side to cool water. Although I do have a 2.5 evap and a large blower motor out of my parents house. So maybe I'll just hack that all together to play with first.. I need to find a pulley to put on the Kubota to drive the compressor..  I'll be posting picture soon

So I might actually get around to working on this. The house I just bought has a detached garage. It had its own separate electric meter that cost 40$ a month just for that meter.. Needless to say my garage is off grid and running on my 1kw solar array. I currently don't do much in there as we are about to get married. But after that I'll be getting my Kubota generator up and running. I'll be attaching the z482 to a 5kw gen head to feet into my magnum 4424 inverter with built in charger. That should pretty we'll hold me over for a while. Somewhere in that time all be setting it up for chp duty. Eventually I should end up with about 3kw of solar.then I'll add  some large pex and some wire to run from the garage to the house. I'll then have a secured load panel set up in the house that will run off of the solar and gen as much as possible.

Cool but it looks pretty complex lol

http://thecodeinn.blogspot.com/2013/07/tutorial-weather-forecast-in-python.html?m=1

That's an older post but it gives a general idea of how to get weather data from the web using Python. I have yet to try it on my raspberry pi but hopefully sometime in the next week I'll get around to it

So I've started playing with programming Python. I actually kind I like it. Anyway I started writing down possible inputs and outputs for this controller idea.

"Inputs" or rather variables?
1 cloud cover/sun/rain
2 outdoor temp
     Both will be looked at in a few hours into the future to help decide how to continue.
3 what else?

" options to charge and replenish"
1 solar panels
2 prime mover
         Exhaust/coolant heat recovery
         Dc charger
         Ac generator
         Possible engine driven heat pump?
         Air compressor?
3 small generator
         Dc charger
         Exhaust/coolant recovery
4 heat/cool source
         Oil burner
         Pellet burner/wood chip/ biomass
         Outdoor wood boiler
        ?

Then we have things like calculating btuh in a storage tank and the btuh loss of the home or building.
This will also be a variable for what system to run to get things back to charges or full level.

Anything I'm missing?

Thanks for the input guys. Well I agree with the pi being the better option for a controller. I had planned on it being a "headless" system. IE not monitor hooked up and just use a android based tablet for control/monitoring. That should lower power consumption. I also like the idea of having one main controller and then having arduinos controlling the individual sensing of the different parts of the system.

As far as battery monitoring al (he made some nice arduino based small engine controllers on the site) has been working on a can system that will allow most of his creations to talk to each other. I also have some of his engine controllers on hand but aren't assembled or in use yet.

I was talking to a guy at work who is an electrical engineer and also loves playing with arduinos and pi's about my controller idea and he didn't seem to think it would be to difficult to pull off. He mentioned you can actually pull weather data from the web in structured info that can easily be used in a program. I had no idea you could do that! So that makes the prediction of the weather much easier to handle. No need for light sensors or temp sensors.

He seemed like he would be willing to assist in the programming of such a device. Although I'm in the process of trying to get my house ready to sell (finishing up a bathroom remodel) so I just don't have time to mess with it at the moment. I kind of started this thread just to try and get the creative juices flowing. Try to get input on what features would be nice to have? What parts of the overall system to monitor and or use for the logic or "ai"

I think with being able to pull the weather forcast from the web and actually have usable info from it will be a huge step in making the project simple, or somewhat simple. Pull the forcast for the next few hours and decided what gen to run or if it's even needed because the solar will take over on the batteries.

So keep up the discussion I'd like to see what you guys would like to have intragrate with this

Yes that is one way to do it. But I guess my thought was to kind of be able to predict what was going to be needed by checking the weather. But then again I wonder if that would really make a huge difference.

Although something I've noticed with my best thermostate that I really hate. When it's  8:58 and it calls for heat but I have a temp change set at 9 it will kick the furnace on and then kick it right back off at 9.. Sooooo anoying.. That is the kinds of thinks I was trying to avoid with this logic and checkin the weather.

But I even had another idea on something to add into the logic part. Peak energy usage in the house ie cooking dinner in the afternoon or breakfast in the am.

Ok well I haven't designed it yet and I'm not really all that great with programming. But I just wanted to start a thread to get some ideas on what we would like in a controller. Now I'm not talking about controlling an alternator or anything like that I'm talking about putting some logic behind a complete chp system. Things like the generator or in my case it will be generators. I have a larger one capable of 7.5kw and a small one good for about 3kw. I have solar panels and a fairly large battery bank of 24v at 840 amphr. Also I plan to build a waste oil burner to heat water.

So this is the part I want input on. The "logic" part. M

Recently I've found out that you can use an arduino or a raspberry pi to check the weather. More importantly it can tell the temperature and if it will be cloudy or rainy or sunny.

With this in mind we could have it look at the battery state of charge and the temperature of the water storage tank. With that information we can take into account when the sun will come up and approx how much sun we will get.

If it will be sunny soon and the batteries are "low" we can wait a little while and see if the solar panels start charging the batteries. If they don't after x amount of time we fire up the gen.

Or if we know it's going to be cloudy we just fire up the gen.

Also if the batteries are full but the storage tank is cold we can fire up the boiler to make some heat.

In theory we can maximize our efficiency by not running something when the solar will be able to take care of it.

Hopefully my rambalings make some sense. If anyone has other ideas or things to control please add it or if you have a better way to improve the logic have at it.

Just want to get the ideas flowing and see what other stuff I'm missing.

Rob  

Edit.. Could even develop a btu needed chart for your home so the control could know how long the water tank could keep your house warm at the given outside temp.

Ugh still 5.4 volts..

Hmm ill have to look at the specs a little closer on the new cap I got. But I was just soon some more digging for parts and I can't find anything worth while for this gen head. So to be completely honest I don't know if it has Brushes or not.. Couldn't get it apart far enough to tell. I looked in all the wholes I could and didn't see any.. But I did find some info that suggested trying to re charge the capacitor field in a service manual. Basically disconect the cap and start gen connect 12v to leads for 2 sec turn gen off reconnect cap and start again.. Ill try that when I ge home

So I'm torn between 3 inverters.. Outback vfx3524 magnum ms4024pae and the Schneider conext sw4024..

Leaning more towards the magnum or Schneider do to the pass through ability with an ac generator. And further leaning towards the schnieder do to it's price point..

Thanks for the info.. Keep me posted on your project..

ill look into it.. ive been trying to get the ac generator that doesnt output the correct voltage working.. ive replaced the capacitor and tried to re charge the field with no luck.. still outputting 4.7v. its just a 120v unit. its spinning at 3700 rpm. its a little fast i know but it should be outputting more then 120v. guess the next step is look at the brushes? also the neutral wire was connected to the chassis of the gen head when i got it is that correct? seems funny to me. this apu is a carrier pc6000. i cant find to much info short of a few pdf that show the normal what to check and how to install it info.. nothing i need..

Thinking something like this for the exhaust ex

http://www.pirate4x4.com/forum/general-4x4-discussion/324151-another-homemade-onboard-shower.html


Anyone know if copper does anything weird with exhaust gases?

Well I'm just not sure if the engine will provide enough btu to keep the house warm.. So the heat pump was just to add some btu to the tank. But my main goal is to have the alt set up and working on the motor by winter time and have a new larger inverter running.. At that point ill be able to get a better idea of the btus that I can harvest from te motor

Speaking of inverters my original plan was to use the outback vfx3524 inverter. But I'm thinking now of going with the magnum ms4024pae as it has the ability to use the inverter power and the gen power at the same time to increase power handling. Also it outputs true 240v power basically 2 2kw inverters. My only fear with that is 2kw is kind of small. Now my intention was to be able to run as many of the normal electrical loads as possible so that's where the magnum inverter idea comes in.