12Volt ......START

[lucas]

Well here goes,

   I'm new at this and don't know a whole bunch about motor theory, but from what i see you guys build and what i read from some old basic electricity text books, I'll give it a shot.

    I want to build a basement where my 14' tall crawl space is, and I want to use all my electricity from Wind,solar,and possibly sterling engine production(12volt systems ).My goal is to go all HOME BREW with the intent to go completely OFF GRID. With that in mind I still have some more digging to do, and concrete to lay.

    All the help , ideas , drawings , books , and  links would be greatly appreciated.

                        Luke

[scottsAI]

Lucas,

Need to ask questions a bit more focused.

Searching web for general stuff works better. And here.

Skip the Stirling engine. Practical engines are expensive, very difficult to make. Looks simple enough. Steam engine are more practical.

Have fun,

Scott.

[RandomJoe]

My first thought is, "why 12V?"  Do you have a pre-existing reason to select that voltage?

If you don't, I'd suggest going for a higher voltage - 24 or 48V - especially if you want to take a house completely off-grid.  (Although just what that entails could vary - do you intend to completely forgo an inverter and 120VAC appliances and such?)

In my case, my primary usage is already 12V (ham radio bench) so I chose to stay with that.  Were it not for the radios, I'd definitely have chosen a higher voltage - probably 48V.  Even as it is, I still occasionally consider that idea.  I just can't quite bring myself to run an inverter then power supply back to 12VDC for the rigs, though!

Raising the voltage drops the wire size requirements considerably, as the amperage to do a given amount of work goes down.  It also means a small voltage drop isn't the huge killer it might be at 12V.  I am frequently amazed - and frustrated - at how large of a wire I wind up needing for some tasks just because of voltage drop.  

It can also mean more power from a given device in some cases.  Solar charge controllers often can run at 12, 24 or 48V - but will pass the same amount of current at each one.  So my 80A charge controller will only supply 960W max on my 12V system, whereas if I were to change it to 48V it could supply 3840W.

[AbyssUnderground]

You could get a 48v -> 12v converter rather than running an inverter to run a PSU. Much more efficient.

[RandomJoe]

I had thought about this at one point.  A bit of searching only turned up primarily low-wattage units.  I'd need something that could handle 35-40A at 12V minimum.  The only higher-power units I found were some Samlex ones, but they are only 24V->12V.  I also wondered about possible noise generated by the electronics - wouldn't do to trash the RF spectrum while trying to use my ham gear!

Do you know who makes some higher-power 48V-12V converters?  Perhaps I'm just not using the right description in my searches...

[lucas]

Thanx

    I also considered a 48 volt system,but I'm still very new at this . Since writing last I looked at alot of the helpful info. on ya'lls site and relized I need to compile more data and move foreward when and only when I feel more confident.

    SO....... with that said I'll try to keep my chatter to a minnimum, and ask more direct but somewhat naive questions.

    You'll here from me from time to time. If my questions sound stupid please know I'm only self tought and not educated beyond highshool.

                            Your website is informative and greatfully appreciated

                          Lucas

                          Hansville, Washington