generator and PVpanel, setup suggestions?

[grayski41]

Hi all, great posts,
I have a generator that i use for power tools gives out 230v or 12v, and 900watts of solar panels that i intend to put on the roof this summer. Any ideas how i might link the two, i thought i might be able to charge the batteries (size to be decided) from the solar panels and top up the batteries on dull days (plenty of them in france) using the generator, How would this affect my Batt. calcs? and whats the most economical way to do this?

thanks

[Sunking]

whats the most economical way to do this?

thanks

Do not use the solar panels. You are in France and have 1 million years of nuke energy.

[Mike90250]

Do not use the solar panels. You are in France and have 1 million years of nuke energy.

Good one. If you have power lines nearby, use them. If not, post back.

Solar and cloudy areas are not a great combo. You will be running your generator a lot to keep batteries charged up.

[Perry]

It sounds like he already has the panels...

Grayski,

If you are hooked to the grid already, the you might consider grid-tie inverter which eliminates the need for the batteries.

When the grid goes down, it's time to fire up the generator.

[grayski41]

I am fully aware that the most economical way to get electric is on grid, that was not my question, 'the most economical way to do this?' related to the proposed situation as described.
Its a question of independance we have a very low elec. consumption. We have a wood burner to heat water and the house and solar collector panels in the summer. We grow and preserve (not freeze) alot of our own food. We only require elec. for this lap top, lights, (led & cfl) central heating pump and my workshop which the generator (bio-diesel) takes care of. I was hoping to make the generator more efficient with the addition of batteries. I have already invested in the panels and have a seperate standalone sewage pump and garden irrigation sytem working for 2 years.
Not really the place to get political

Correct - not the place to get political so political comment removed.

[Perry]

Hi all, great posts,
I have a generator that i use for power tools gives out 230v or 12v, and 900watts of solar panels that i intend to put on the roof this summer.
thanks

I'm new here, but I'll take a stab at it and let the experts correct me.

I think you should design your battery requirements around your 900 watts of PV panels and just use the generator (with a 3 stage charger) when the batteries drop below 50% State of charge.

I'm thinking about 800 amp-hours worth of (12v) battery storage would be about right.

[Independent Patriot]

I am fully aware that the most economical way to get electric is on grid, that was not my question, 'the most economical way to do this?' related to the proposed situation as described.
Its a question of independance we have a very low elec. consumption. We have a wood burner to heat water and the house and solar collector panels in the summer. We grow and preserve (not freeze) alot of our own food. We only require elec. for this lap top, lights, (led & cfl) central heating pump and my workshop which the generator (bio-diesel) takes care of. I was hoping to make the generator more efficient with the addition of batteries. I have already invested in the panels and have a seperate standalone sewage pump and garden irrigation sytem working for 2 years.
Not really the place to get political

Correct - not the place to get political so political comment removed.

It sounds like you have a great set up grayski. I'm striving toward self sufficiency and independence from the grid too. Self reliance is very gratifying.

Like Perry, I'm a solar rookie also. However, it sounds like you have some real possibilities with your current equipment.

What exactly do you want to run from you solar system?

Power Tools
If you want to run power tools I'd suggest purchasing as many battery operated power tools as possible and use the PV system to charge the batteries. That's one way to easily reduce power consumption.

A proper inverter coupled with an adequate battery bank should take care of your common AC power tools if you're only using them for short periods of time for small projects. If you have large AC power tools that will be running for extended periods they could draw ALOT of power from you battery bank thus requiring a large battery bank.

Laptops, Lighting & Etc
Running your lap top and lighting (with CFL's) should be easily achievable without a massive battery bank. Furthermore, you could purchase other 12v appliances to replace appliances you currently have. There are ceiling fans, coffee makers and other items available.

Heating & Cooling
The killer is the heat pump.....Solar/battery support for the heat pump will probably out of the question. I would look to alternative methods or heating and use your bio-deisel for the REALLY cold days. I've heard that corn can be an efficient fuel source...?

Another idea is the use of a 12v bed heating pad. It could be used to keep you warm on REALLY cold nights in supplement with your alternative heating sources.http://www.backwoodssolar.com/catalo...ces_dc.htm#BED WARMERS

For cooling (if it gets hot where you are) you could check out 12v evaporative coolers. I've heard that they are surprisingly effective. http://www.backwoodssolar.com/catalo...nces_dc.htm#12 VOLT EVAPORATIVE COOLER

Sorry I cant help you with any technical advice as to what size battery bank you should have. I'm more or less here for moral support until I learn more...lol!

If you list your solar goals in specific terms the guru's on here should be able to give you more concise answers.

[Sunking]

We only require elec. for this lap top, lights, (led & cfl) central heating pump and my workshop which the generator (bio-diesel) takes care of. I was hoping to make the generator more efficient with the addition of batteries.

Not possible with a heat pump period unless you can build an extension for you home to hold all the batteries measured in TONS and an enourmous amount of solar panels to go with it.

[Mike90250]

..... I was hoping to make the generator more efficient with the addition of batteries. ...

Done this way:
fire the genset up when batteries are @60% (or 70% if you know it's going to be a cloudy day) charge the batteries at full tilt - diesels like to be loaded, if too lightly loaded, they carbon up (wet stack). When your batteries reach 80- 85% full, or the charge controller switches from BULK to Absorb, switch off the genset, and let the solar take over the long, lightweight charge portion

Additonally, when running dishwasher, washer/dryer major appliances, run the genset if it's cloudy.

Running genset for the 30 min every AM, can bulk the batteries, make your toast, and then let the solar do the rest.

You will need a good charger. I use the charger in my XW6048, hooked to the 240V gen, and can put 2500 W in ( @ 55v 45A ) from my 3KW genset.

If you are only using a 12V system, a diesel genset is WAY overkill, you will wet stack the engine.

[Perry]

Charging Cordless Tools on Inverters

I
Power Tools
If you want to run power tools I'd suggest purchasing as many battery operated power tools as possible and use the PV system to charge the batteries. That's one way to easily reduce power consumption. .

Seems like I tried recharging my cordless Porter Cable Batteries on my inverter and they acted weird? Didn't I read somewhere these batteries have a problem on a mod. sine inverter?

[grayski41]

Thanks guys for all the input, some great sugestions.
Just to clear up one point, I have a central heating pump which pumps the hot water from the wood burner round the radiators and hot water cylinder, 10w. Not a Heat pump which is as Sunk has pointed out is a far more hungry beast with debatable efficiency.

Thanks mike for the suggestion i have looked at the spec. of your xw6048, wow nice piece of kit. I have a Kipor Diesel KDE6700Ta (4500 Watts) Genset it does have a 12v output but would i be better buying a good quality 3 stage charger to run off the 230v output? with a manual change over swith, to switch between the panel/chargecontoller and the genset?

[russ]

I like your heating solution - good one.

One correction though - A heat pump is a very much known item and for many they are a good solution. The efficiencies are a matter of record - no conjecture involved.

Russ

[Independent Patriot]

Seems like I tried recharging my cordless Porter Cable Batteries on my inverter and they acted weird? Didn't I read somewhere these batteries have a problem on a mod. sine inverter?

I'm not sure Perry. When I was a contractor I charged my power tool batteries from a cheap inverter which was installed in my service truck. I never had any issues though.

Would a pure sine be better for charging?

[Perry]

I'm not sure Perry. When I was a contractor I charged my power tool batteries from a cheap inverter which was installed in my service truck. I never had any issues though.

Would a pure sine be better for charging?

I only tried charging my Porter Cable 18 VDC batteries once. It just seemed like the charging was finished way too soon. I never really determined if it worked or not. I just seemed to remember that I read somewhere that mod-since wave inverters will not properly charge SOME cordless tools.

[Mike90250]

..a Kipor Diesel KDE6700Ta (4500 Watts) Genset it does have a 12v output but would i be better buying a good quality 3 stage charger to run off the 230v output? with a manual change over swith, to switch between the panel/chargecontoller and the genset?

Yes, the 12V output from gensets is usually pretty wimpy, and a sturdy 120/240 v charger will recharge a bank much more quickly