Learjet's dodgy 12V solar installation

[Yobbo]

hey Learerjet, how did you go with the cyclones??? did your flower pots get blown away????

[vinal]

Learjet that's very good way to save Money, but how much did it cost you to buy everything?

[Learjet]

I'm replacing the flower pots with metal brackets now. The pots were just temporary. Fortunately the cyclones were a long way north of here and we didn't get much from them.

The cost: dunno. I think I paid about $3.00 per watt for the panels. Some were cheaper, some dearer. Probably take me a few years to recoup the outlay.

The point of the exercise was two fold. One - to save a bit on the power bill and two - to have power independently from the grid. It ended up turning into a hobby so that's 3.

It's annoying losing stuff in the fridge when the power goes out for ages and having no fan or lights. Now I have a 12V fridge. I suppose I could run a generator, but I hate smelly, noisy, greasy, petrol guzzling IC engines. I don't think much better of gas.

Future plans are for a battery electric mower, recharging the battery from the panels. A bigger 12V fridge - freezer. My research has discovered that Engel is radio quiet. And maybe I will switch to a laptop computer. They consume less power than a desktop, though they are more expensive to buy for equivalent power.

Would love an electric car.

Of course I will need more panels to power all that.

Edit, by the way, power usage habits for stand alone solar is rather different to grid connect. With grid connect it's best to use as little in the day as possible to get the highest sell price per kW. I've found with a battery charge system it's best to use the excess afternoon power, after the battery bank has been recharged throughout the morning. Unfortunately much of the excess is wasted. Usage also depends on the clouds and weather. Probably something the average person would rather not be bothered with.

[Guiseppe]

... Would love an electric car. ...

I have seen an electric Vespa like motor bike - no idea what voltage though.

Mum had an electric tricycle that was 24V.

[Learjet]

I had something in mind more like this...



In my dreams of course.

[wal1]

I'm replacing the flower pots with metal brackets now. The pots were just temporary. Fortunately the cyclones were a long way north of here and we didn't get much from them.

The cost: dunno. I think I paid about $3.00 per watt for the panels. Some were cheaper, some dearer. Probably take me a few years to recoup the outlay.

The point of the exercise was two fold. One - to save a bit on the power bill and two - to have power independently from the grid. It ended up turning into a hobby so that's 3.

It's annoying losing stuff in the fridge when the power goes out for ages and having no fan or lights. Now I have a 12V fridge. I suppose I could run a generator, but I hate smelly, noisy, greasy, petrol guzzling IC engines. I don't think much better of gas.

Future plans are for a battery electric mower, recharging the battery from the panels. A bigger 12V fridge - freezer. My research has discovered that Engel is radio quiet. And maybe I will switch to a laptop computer. They consume less power than a desktop, though they are more expensive to buy for equivalent power.

Would love an electric car.

Of course I will need more panels to power all that.

Edit, by the way, power usage habits for stand alone solar is rather different to grid connect. With grid connect it's best to use as little in the day as possible to get the highest sell price per kW. I've found with a battery charge system it's best to use the excess afternoon power, after the battery bank has been recharged throughout the morning. Unfortunately much of the excess is wasted. Usage also depends on the clouds and weather. Probably something the average person would rather not be bothered with.

Mate I can relate, living in Rockleigh SA, off grid system when its nice an sunny and under 30 degrees, all is good. Hate it when I'm having a shower an it cuts out. Have a back up genny, so trot out covered in suds to start it. Cost to put grid power on, in excess of $65k, so live with it.

[Yobbo]

sorry Learjet, with them I was thinking more of a car like this would be suitable, and affordable,

But as battery technology gets better and cheaper, you never know, there are some pretty good home made battery powered cars out there

[MaXiLeeCH]

G'day Learjet,
My mate uses both the 40 and the 80 litre Engel 12/24/240V fridges and they are both RF quiet on all bands from HF to 70cm.
He uses them on 24V as they are more efficient than running them on 12V and they are in a Coaster Bus which is all 24V, including the house batteries.
(He uses a voltage reducer for the HF / VHF / UHF rigs.)
How do I know?, I did all the wiring and setup for him.

[MaXiLeeCH]

I might add that I am following these posts with interest, I currently use about 500AH of battery power for my radio's at home and I'd like to go much further with the 12V system.

The LED strips seem to be a pretty good idea to me though I am concerned about the CF lights and their RF noise.

Solar panels are interesting but here in Innisfail we don't get enough sun in the wet season to warrant them.

Ditto for the solar HWS's too.

I do have access to more batteries (2V, 250AH) at little or no cost but I need to figure out how to charge them at low or no cost. (Any idea's anyone?)

[Learjet]

Thanks Maxi for the info on the Engel! Much appreciated. Looks like there will be an Engel in my future then. The Waeco is a good backup but it produces radio noise from DC to daylight!

The CFL's are noisy. I prefer to use the LED lights. We just make it all the more difficult trying to run a radio quiet solar setup don't we? lol.

For charging various batteries I use a battery charger I got from Hobby King. It's a Turnigy Accucell 8150.

It will charge any lead acid battery from 2 - 36 volts @ up to 7 amps (user adjustable) and any number of other battery types, lithium, nimh, nicad etc with an input voltage of anything from 11 to 18 volts. It's a really versatile little charger for any battery. Only cost me $42. There are 10 amp charge models also.

They have a great lineup of chargers here.

[MaXiLeeCH]

Your welcome Lear........
Currently, (pun intended) I use my 30Amp 13.8V supply to charge my gel cells and it seems to work ok.
As their recommended intial charge rate is 10% of rated capacity it works out at 25A (Or 50A if both sets are in parallel) initial charge rate and 13.8V is their recommended float voltage so it seems that all is good so far.
I do have a 'Lab' type variable voltage (1.5 - 30V) and current (0.1 - 3.5A) supply which I use if I want to slow(!) charge the batteries but after a far amount of radio playing it can take days to weeks to pick the batteries back up with that.
So, I tend to use the high current supply.
For information the batteries are ex Telstra exchange 2.1V 250AH gel cells, I currently have 12 here for 12V @ 500AH and I hope to at least double that AH number soon.

I can run my Elecraft K3 for weeks at a time before a recharge is needed.

(I love my K3!)

[Learjet]

So you're not charging them with solar panels at the moment? My mistook, I thought you wanted a 12V in X volt out charger to charge single or odd number cells.

For cloudy days you have to go for overkill with 12V solar. My output is 1/3 of regular output today due to cloud, but I factor that into my usage.

With 1kW of panels you could still put out 20 amps even with cloud.

[MaXiLeeCH]

Ahhh, ok
Thanks for setting me straight on the panels Lear..... does anyone know where I can get some cheap panels then?
I guess that even a 5 -7A charge rate would be better than nothing.

[Yobbo]

MaXiLeeCH

With all the cyclones you have up there maybe a 300km rated wind generator might be more useful

I have a 40L engel and when my HF radio was running off the same battery in the 4wd I could hear noise on HF, when using a vechile mounted antenna, either a codan 9350 or tapped, but when I used a dipole there was no noise mainly using 20m 40m and 15m

I was using a ic706MK2g / 9350 then a TS480sat / tapped

[MaXiLeeCH]

hi Yobbo,
with both fridges running on 24V and the rig (Elecraft K3) on HF / 6M no noise was detected at all, using HF beams, wires and verticals.
I 'spose that there maybe a few fridges out there that are a little noisy but by and large I've not heard hardly any complaints about the Engel's for noise. (Or anything else for that matter, they rock!)

[Learjet]

I'm still producing 7 - 8 amps in this sort of cloud.



I got most panels from ebay. Don't buy from LHP. They are under spec.

[scrappydoo]

I'm still producing 7 - 8 amps in this sort of cloud.



I got most panels from ebay. Don't buy from LHP. They are under spec.

i like the idea of the Led strips and have bought 2 for under the house, work really great and don't take up any head room..powering them from a 12v power pack just now but would like to hook it up to a battery and charge with a panel. lights don't get used much

what kind of cable/wire did you use to hook up to the solar system and where did you get it from?

cheers

[Learjet]

what kind of cable/wire did you use to hook up to the solar system and where did you get it from?

Controller to battery uses RG-213 coax for the negative terminal and 2 pairs of heavy duty extension cable with all wires joined for the positive. That should carry some serious amps. Extension leads came from the recycle centre.

The solar panels to the combiner box I am using twin flex automotive cable. I think they claim this does 50 amps. I have wired each panel separately so it really only needs to carry 4 amps. The overkill is for reduced voltage drop and to cope with future system upgrades. If I get to 1kW the system will need to cope with 50 - 60 amps continuous. However I'm thinking of splitting the system into two parts. 500 watts for the computer and radio room and another 500 watts to run a fridge.

Oh and I now have a 24V battery mower! It will be charged by solar panels of course. Got a floor display model cheap. I've already pulled it to bits and will be converting the 2x12V 20ah lead acid battery system to a 6s2p lipo battery saving 13kg in weight. It will also have more power since lipos' voltage sags less than lead acid under load and can deliver up to 350 amps! The mower batteries could be used for solar panel battery bank number two (12V 20ah batteries x2 in parallel = 40ah). I may eventually swap the motor to a brushless model aircraft motor which will make it the most powerful electric hand mower on the planet! *insert evil laugh here*

[Learjet]

Mowed the whole block today with the battery mower. Only one LiPo arrived so far (getting them in different orders) so had to recharge it a few times to get the whole lot mowed. Remember I have a large block.

Here's the mower. It's a homelite 24 volt battery model from Bunnings.



A size comparison between LiPo and SLA. No wonder people hate this mower in stock form. It's a heavy pig running on these SLA batteries. On the LiPo it's lighter than my 3.5hp Rover.



On top of the mower I mount a watt meter / power analyser. It's quite a nifty little meter that fits inline with the battery and the rest of the circuit. It reads volts, amps, watts, peak amps, minimum volts, watt hours, peak watts and amp hours.



According to this meter it takes about 600 watt hours for me to get the lawn mowed. All charged from the solar panels. No electricity from coal fired power plants or fossil fuels were used in mowing my lawn. Which all counts for nothing as I had to run the air conditioner harder to cool down in this 36 degree heat.

[Guiseppe]

I had something in mind more like this...



In my dreams of course.

You and me both - just read a short report in the NRMA mag.

In my case sell the house and buy it - wait a minute then there would be no power point ...