the Otherpower.com Discussion Board || Comments Charging Batteries (Efficiently) with a Diesel Generator

Front Page - [Homebrewed Electricity-- (wind) (solar) (hydro) (steam) (controls) (storage) (mechanical)] - Classifieds - Site News
Everything - Newbies - [Remote Living-- (housing) (heat) (light) (water)] - Rants & Opinion - Diaries - Our Products

Charging Batteries (Efficiently) with a Diesel Generator | 23 comments (23 topical, 0 editorial)

Re: Charging Batteries (Efficiently) with a Diesel (3.00 / 0) (#13)
by 97fishmt (mlawson97fishmt@msn.com) on Fri May 9th, 2008 at 11:33:12 PM MST
(User Info)

O.K. I just thought you were going the cheep route. I too would like a nice diesel
genset and all that goes with it. I know lots of people here do. Just having your inverter kick on the generator to charge because of insufficient charge may not be
what you are after if you are not there. You did not say if this was a residence.

You did say it was remote. For a large system like you are describing get the
diesel genset and the fuel delivery to with it and you will better off than
most people in the city, if you enjoy it , but it will cost you quite a bit per
kwh of diesel compared to the grid.

[ Parent ]

Re: Charging Batteries (Efficiently) with a Diesel (3.00 / 0) (#14)
by Flux on Sat May 10th, 2008 at 01:45:19 AM MST
(User Info)

I haven read all this and the comments but basically I think you have contradicted your own intention in the question.

The most efficient way is with a directly connected generator and this generator would need to be compatible with battery charging requirements. I couldn't see you finding such a thing commercially suitable for use at 48v.

"The alternator's output is stepped down using an iron-core AC Transformer, then run through a rectifier to output DC current to charge batteries."

That answers your own question, that is not direct connection, you have included a battery charger even if simple and home built. Once you go the battery charger route then your original question goes out the window. The new issue is what is the most efficient battery charger.

Beyond this the issue comes down to so many factors that I can't be bothered to wade through it. The high tech battery chargers are primarily designed for mains use and their main purpose is to look after the batteries. On mains they take what is needed to do it.

Running these things from generators alters the equation where you are looking at fuel economy load etc and in most cases they are expensive and far from ideal but they do give ideal charging characteristics.

Your transformer and rectifier if using a suitable transformer will be as good as the expensive high tech things but will not be as good as a direct 3 phase alternator rectified and set up for battery charging directly at 48v.

Single phase is dreadful for battery charging.

You will have so much advice that you will be no wiser in the end.

Flux

[ Parent ]

Re: Charging Batteries (Efficiently) with a Diesel (3.00 / 0) (#15)
by Usman (usman@aljeathen.com) on Sat May 10th, 2008 at 07:20:42 AM MST
(User Info)

Thanks Flux,

Great explanation!

The reason for the inefficient iron core generator, mainly not to mess up with a readily available 220V single phase generator, by simply running a wire from it's output socket to a 1:4 or 1:3 transformer, so that when the resulting single phase AC passes through the rectifier, it gets within a reasonably efficient charging frame.

Yes, single phase & iron core transformer, both add to inefficiencies. So, what about directly connecting the high A/C line (220VAC) into the battery pack (after rectification)? Wouldn't that be comparatively efficient?

I know that a 3-phase PMA turning within the 50-60VDC Voltage frame is the most efficient way to go, but that would need some re-engineering work to an off-the-shelf generator.

It is preferable to either go for no retrofitting at all, or designing a completely custom-designed & built engine/generator.

To comply with the second route, any comments on the automotive diesel engine's retrofitting with the right PMA running at idle speed or just above idling speed! Wouldn't that be most efficient from both aspects i.e. the fuel consumption as well as battery charging? Also easier maintenance, widely available parts, cheaper, etc.....

Thanks.

[ Parent ]

Charging Batteries (Efficiently) with a Diesel Generator | 23 comments (23 topical, 0 editorial)

Menu

· create account
· How to use the board
· FAQs
· search the board
· Google search the board
· Old Otherpower Board

Login

Make a new account

Username:

Password:

You must be a registered user to post here. It's easy and free, and the link is on the upper right side of your page.
All trademarks and copyrights on this page are owned by their respective companies. Postings are owned by the poster, but may be deleted or moved at the ADMIN's sole discretion. The Rest © 2003 Forcefield.
You can Email the board ADMIN here. PLEASE include the username you signed up with!