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Solutions for loadshedding


Rocket-Boy

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Off grid and grid tied is very expensive.

I have opted for separate lights which run off a battery. I want to ad a solar panel to this, and run my fish tanks. The fridge and freezer I am considering a UPS. I think thats around 10k for the ups.

Solar panel would probably cost around 2k or more depending how much batteries I am gonna run. Solar wiring is around R350 for 20m. I reckon I am in a ball park number of 15 to 20k. I wont incorporate into the grid with the lights. My idea is basic lights for the house. Should we have visitors or a family gathering then we can use eskom lighting. I am happy to leave the fridge, freezer, tv and computer on eskom as well. I have a laptop and wifey has a tablet. We can charge these in our cars or off the battery pack I have for the lights. It is a gel something battery. Been going for a couple of years now. 

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Yes when its just used with battery backup then they operate in UPS mode, but when solar is introduced then all grid-tied inverters have to turn off when the grid is off. Its designed that way to protect technicians working on the lines. Even with the export functions disabled they still behave that way.

 

 

Mine definitely does not switch off - I have a small cottage elsewhere with a smaller offgrid (but grid tied) system.  Also doesn't switch off - export function off on both

 

I'm no expert that's for sure so I couldn't tell you how this is achieved

 

I turned off the export function as we had an old meter which we spun back so far (for free) that I got a visit from the municipality

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Mine definitely does not switch off - I have a small cottage elsewhere with a smaller offgrid (but grid tied) system.  Also doesn't switch off - export function off on both

 

I'm no expert that's for sure so I couldn't tell you how this is achieved

 

I turned off the export function as we had an old meter which we spun back so far (for free) that I got a visit from the municipality

Sounds like a hybrid setup which is great.

You bring up a very valid point though which is really important. On on older account based meters vs pre-paid meters.

With the older meters they will run backwards as you mentioned which really confuses the heck out of the municipality! They dont like it much and they wont "pay" you for backfed kwh.

With pre-paid meters its even more messy, if you export to grid on those meters then the vast majority cant tell the direction of current flow, so what happens is you end up using units for each kwh you push back!!!

A lot of inverters use a clamp type hall effect sensor to measure your main grid link to make sure it isn't exporting. That would definitely be desirable if you have a pre-paid meter.

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We are also looking at going off the grid totally.

 

Could end up being a costly outlay as we are a family of 4 as well as a self contained cottage that our domestic and her husband and son stay in. 

 

Would also need to run a pool pump (not a small pool) as well as the pump for the borehole.

Pumps are pretty rough on systems because of inrush current.

I have seen a lot of people describing their setups on youtube when they went fully off grid and built a house in the sticks.

All of them had pumps to get rain water for flushing toilets etc and all of them said that if anything else is on at the time it would max out or overload their inverters.

 

The ideal scenario from a cost perspective is to deal with the simpler loads like lights and plugs. The large energy hogs should probably stay grid tied.

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I'm only putting this here because I know the guys and have worked with them for many many years, but I have no affiliation or incentive to do so, but it might be worth checking out for some of the guys who are interested in a system.

 

mC5liZt.png

 

https://solecsa.co.za/packages-solar-power-and-battery-back-up-solutions/

I have been eyeing the Alpha Smile5 for a while, it would be my first choice if money wasnt an object.

The whole modular system with products designed to work together is a winner.

The downside is that a mid point system like a 10.2kw setup will cost around R100k and that is before installation or solar panels!

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I am looking to set up lights for outside mainly for security reasons and maybe some inside as well .

If you do lights only that can work of DC you do not need an inverter, My question is , Can you use any battery? Like a car battery for instance to be charged via a solar panel?

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I am looking to set up lights for outside mainly for security reasons and maybe some inside as well .

If you do lights only that can work of DC you do not need an inverter, My question is , Can you use any battery? Like a car battery for instance to be charged via a solar panel?

Yes, I have some 12v LED "worklights" They are small, 10w but extremely bright. I got them from safari center. But you should be able to get whatever from any car shop.

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Pumps are pretty rough on systems because of inrush current.

I have seen a lot of people describing their setups on youtube when they went fully off grid and built a house in the sticks.

All of them had pumps to get rain water for flushing toilets etc and all of them said that if anything else is on at the time it would max out or overload their inverters.

 

The ideal scenario from a cost perspective is to deal with the simpler loads like lights and plugs. The large energy hogs should probably stay grid tied.

it's not cheap but you can get a VSD pump (variable speed drive) These pumps build up slowly so the initial "power grab" isn't that high

 

That said on my smaller system I have 2 small pumps purchased from the farmers co op for 2 grand each and they don't seem to suck too much power

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I have been eyeing the Alpha Smile5 for a while, it would be my first choice if money wasnt an object.

The whole modular system with products designed to work together is a winner.

The downside is that a mid point system like a 10.2kw setup will cost around R100k and that is before installation or solar panels!

have installed a smile5 with 2 batteries.

 

it works really well.

real chinese, the manual is basically useless so had to get a bit of guidance from distributers. but it has perfomed well now that it's configured. They say they've been really impressed with systems rolled out and low rate of returns.

 

the cost should hopefully come down too.

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I am looking to set up lights for outside mainly for security reasons and maybe some inside as well .

If you do lights only that can work of DC you do not need an inverter, My question is , Can you use any battery? Like a car battery for instance to be charged via a solar panel?

You can if you go with automotive lights, those are designed to handle a small tolerance of voltage drop as the batteries are depleted. 

You could technically use a car battery but I wouldnt recommend it. Car batteries are designed to give large amps for a short time and are not designed to be run down and charged back up again, it wont last long at all like that.

A deep cycle battery is designed for that purpose and there are some relatively affordable options in smaller batteries.

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it's not cheap but you can get a VSD pump (variable speed drive) These pumps build up slowly so the initial "power grab" isn't that high

 

That said on my smaller system I have 2 small pumps purchased from the farmers co op for 2 grand each and they don't seem to suck too much power

VSD/VFD are awesome with their ability to program soft start and limit speeds and therefore draw.

Im pretty sure that most VFD's are only designed for 3 phase motors though. I know you can get for smaller single phase but then it wants to work on pulse width modulation which can cause weird reactions.

 

I have been looking for a decent VFD for my single phase lathe for a while now!

 

I know nothing at all about those pumps, are they 3 phase motors?

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have installed a smile5 with 2 batteries.

 

it works really well.

real chinese, the manual is basically useless so had to get a bit of guidance from distributers. but it has perfomed well now that it's configured. They say they've been really impressed with systems rolled out and low rate of returns.

 

the cost should hopefully come down too.

I watched a bunch of Aussie reviews on the system, its a big market for Alpha and they get excellent ratings.

I have been watching my consumption over the last month and I just cant justify one yet, will see what happens in the change of season though.

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VSD/VFD are awesome with their ability to program soft start and limit speeds and therefore draw.

Im pretty sure that most VFD's are only designed for 3 phase motors though. I know you can get for smaller single phase but then it wants to work on pulse width modulation which can cause weird reactions.

 

I have been looking for a decent VFD for my single phase lathe for a while now!

 

I know nothing at all about those pumps, are they 3 phase motors?

They are 3 phase but mine came with a control box of sorts converting it to single phase

 

Happy to get you more info or send you a pic of the setup, no reason it couldn't do the same for your lathe

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I watched a bunch of Aussie reviews on the system, its a big market for Alpha and they get excellent ratings.

I have been watching my consumption over the last month and I just cant justify one yet, will see what happens in the change of season though.

what do yuo monitor consumption with?

daily readings or active monitor.

 

i'd REALLY like to look at a low tech solution for monitoring power consumption on prepaid systems.

basically involves a cheap cellphone mounted onto the prepaid box. uses the flashing light (1000 flashes per kWh) into the lightsensor and times it.

 

i could ofcourse do this with an arduino with RTC and a photodiode too. but cheap cellphones are more available.

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