solar system and instalation

**murdock** · 29-Jun-11, 05:05 PM

the problem with solar power is the batteries need to be replaced ever 5 years at over R1000 per battery increasing depending on demand...when the load shedding kicked in they cost almost R2000 per unit...but in saying that depending on how well you look after them...and if you have a couple cloudy days you have a problem...even one cloudy day effects my system because it only charges enough to get one nights worth of power...but i am rotating 6 x 105 amp/hr batteires so i just connect one of the big batteries to the lighting system.

the other problem i have found is the invertor consumes 4 amps of power and the t etc only consumes 5 amps so the invertor is halving the time...if i could find an more enrgy efficient invertor...it would make a big difference...

i am also doing some research into the duty cycle time of batteries...if they can only be cycled to 50 % then you loose about 4-5 hours...where as if the batterry has a 100 % cycle you can us ethe full 9- 10 hours but the invertor switches off at 11.7 volts...so i will need to do more experimenting before i can comment further.

gas is a good backup option...so long as you remeber to refill the bottles and have a standby one

**AndyD** · 29-Jun-11, 07:43 PM

Local power generation and backup power systems that will run you appliances will be too expensive. For a decent pure sine inverter plus the batteries plus an intelligent battery charger you're looking at R25000,00 minimum. I have designed a couple of back-up solutions using batteries and inverters that will deliver approx 20Amps for 18 hrs and the price was nearly four times what I quoted above. As Murdock pointed out, the batteries are a killer and good quality high efficiency inverters aren't far behind.

**Justloadit** · 29-Jun-11, 08:33 PM

You can get a gas operated fridge, they consume approximately 10g of gas an hour I think, so a bottle of gas should run for a month before replacement.

The problem with Lead Acid batteries, is that you must not discharge them more than 40%, as going lower than this reduces the battery lifespan. The lower you go the less times the battery can recover. Discharging a Lead acid completely more than 30 times will destroy the battery. That is why the inverter switches off at 11.7V, to conserve the battery

**wynn** · 30-Jun-11, 01:35 PM

I read an article where a professor at a USA university was experimenting with a system of generating enough hydrogen by solar power then using the hydrogen to run a generator to power the house and a car even on cloudy days.

I'll try find the link and post it here or on the 'green thread'

here it is http://www.suncatalytix.com/

**IanF** · 30-Jun-11, 03:04 PM

Originally Posted by wynn

I read an article where a professor at a USA university was experimenting with a system of generating enough hydrogen by solar power then using the hydrogen to run a generator to power the house and a car even on cloudy days.

I'll try find the link and post it here or on the 'green thread'

here it is http://www.suncatalytix.com/

Wynn here is one base component to generate the hydrogen flame polisher I see it need distilled water to work, but very interesting way to store energy.

**murdock** · 30-Jun-11, 11:01 PM

Originally Posted by Justloadit

You can get a gas operated fridge, they consume approximately 10g of gas an hour I think, so a bottle of gas should run for a month before replacement.

The problem with Lead Acid batteries, is that you must not discharge them more than 40%, as going lower than this reduces the battery lifespan. The lower you go the less times the battery can recover. Discharging a Lead acid completely more than 30 times will destroy the battery. That is why the inverter switches off at 11.7V, to conserve the battery

that what i also thought but apparently the us 130 amp/hr battery can cycle 100%...i dont know how or why just from the info i found on the internetwhile doing some research a deltec 105 amp/hr can cycle 50 % continuously and can go to 100 % in case of emergency...but it is not recomended...a battery is regarded as flat at 10.5 volts and should never go below this voltage.

**murdock** · 30-Jun-11, 11:05 PM

something i noted recently...i could get the dvd player to play a dvd so i tried different dvds...then 2 days later it worked...what i found was that if the invertor is on the dvd player works but will not play dvds...but when the generator is running it works 100%

**AndyD** · 01-Jul-11, 09:36 AM

Originally Posted by murdock

what i found was that if the invertor is on the dvd player works but will not play dvds...but when the generator is running it works 100%

Maybe a power quality issue. Is your invertor pure sine output?

**Justloadit** · 02-Jul-11, 06:56 AM

Hi Murdock,

These fridges usually also have a heater coil to connect to mains and also to a 12V battery. They draw approximately 8 amps or so at 12V, as the heater must be approximately 100 watts to function correctly.

So on a 105Amp battery and a 200Watt solar panel, you should get a good recycling process, but would be tight. If you have a bad sun day then you battery will not charge sufficiently, but you always have the Gas back up in these situations.