I am a bit of a maverick in that I am not primarily concerned with load shedding.

I would like to generate power to keep a lid on electricity bills in the future and not be reliant on
Eskom. And solar is fast developing into a new hobby!

I am pretty good with managing loads (kids have left) and am currently only using around 20KW  (the maximum) a day.
Of course we are not into winter proper as yet so this could rise.  Heavy loads are 3KW geyser/
1 - 3KW heater / Washing machine / Dishwasher / Drier. Geyser currently switched on for 2 hours during the day.

I realise that at this stage Eskom remains the cheapest source of power.

I have a choice of two systems - both are unfortunately only 3KW to stay below the 3.4KW limit and I won't need to replace the existing breakers:

• Multiplus II  48V - quality make - good back up and spares. But expensive and unfortunately  requires batteries to operate. I would probably use lithium's. Couple this to 8 Canadians  335V or 400V. ROI very much long term. Hopefully I could configure the Multiplus to use as little of the battery power as possible extending their life? An advantage of this system is that if Eskom load shedding worsens this winter I would have some power at home.
• Solis - "cheap as chips"  to generate power during the day and use the grid at night. Also 8 panels . No batteries required . ROI  short -  a couple of years.

 

Edited April 24, 20197 yr by Mistral

You cannot go wrong with either make. 🙂 

Thanks!

Are the new Solis hybrids on the Cape Town list as yet?

Edited April 24, 20197 yr by Mistral

7 minutes ago, Mistral said:

Are the Solis hybrids on the Cape Town list as yet?

Jip. 🙂 

http://resource.capetown.gov.za/documentcentre/Documents/Forms%2c notices%2c tariffs and lists/Approved Photovoltaic (PV) Inverter List.pdf

Do they take any type of battery or only Lithiums?

The spec sheet I saw mentioned lithiums.

I see sengen does the new solis hybrid, though I'm not sure if they have stock

 

Here is the manual .pdf looks like it is only lithiums.....

Link towards the bottom of the page

https://solartricity.ie/solis-hybrid-off-grid-energy-storage-solar-inverter/

2 hours ago, Mistral said:

I am a bit of a maverick in that I am not primarily concerned with load shedding.

Knowing what you want is important.

If this is your goal going grid tied is best.

I have said before it's hard to keep up with the pace of solar technology.

So take what I am going to say, from someone who is a present Victron proponent.

There are some things coming to market from Fronius and SMA, that I think will trump conventional hybrid inverters and conventional PV inverters.

I must admit I am still looking into it, but this is what I gather the differences are.

Conventional Hybrid charges the batteries and then the power is curtailed. When a load is switched on the MPPT's start to deliver but the power is throttled again when the load is gone.

There are numerous water heating solutions to try and reclaim this lost production. ( quite expensive, and once the water is hot that's it).

A conventional PV inverter is different to a Charge controller in some ways:

It is normally incorporates two charge controllers, but they are at much higher voltage, so distances to the panels is not limited, like with a CC.

They are a very efficient in making AC for direct use as a CC only makes DC needing a  further hybrid inverter to make AC.

Conventional PV inverters are however less efficient when used for AC coupling to make DC through a charger for later use.

The new market offering seems to incorporate the following features:

A hybrid capabilty with a HV battery, thereby overcoming the AC coupling loss of efficiency, through minimizing the voltage disparity. The battery is now just like panels on the roof.

And obviously adding Hybrid capability without another inverter.

The other thing though is they seem to have embraced energy management though, being wirelessly able to control plug sockets intrusively as well as other loads.

It looks like they have taken the water heating solution to the extremes, so as to optimally manage the batteries, loads and generation and infeeds together without wasting a watt.

So these new offerings, (and I'm not sure of their price) offer:

1. The cost saving and efficiencies of  high voltage and the efficiencies of a PV inverter.

2. Incorporate 2 CC'c built in.

3. Incorporate the equivalent of a hybrid + ESS scheme, ( maybe an external meter required), but have overcome the inefficiencies of AC coupling with an LV battery.

4. Incorporate a far more sophisticated load management system than heretofore available.

I'd be inclined to investigate these offerings further if I was setting out again.

 

 

 

 

Edited April 24, 20197 yr by phil.g00

Thanks for the update!

Keeping up with this technology is challenging.....

2 hours ago, phil.g00 said:

A hybrid capabilty with a HV battery, thereby overcoming the AC coupling loss of efficiency, through minimizing the voltage disparity. The battery is now just like panels on the roof.

First time I saw this was a Tesla+SolarEdge combo. SolarEdge already takes around 380V from the roof (the optimisers on the roof are boost converters), so a high voltage battery essentially tied to this in parallel means that once the sun goes down, the battery essentially does the same thing the PV modules do. The only downside to this setup, of course, is that it's purely grid-tied, can't operate when the grid is down. Obviously this is what the new Hybrids solve.

I get quite nervous around 120v DC , ramping that up to 380v , eeish

22 minutes ago, seant said:

I get quite nervous around 120v DC , ramping that up to 380v , eeish

You should see how wary a live line crew is of earth (0V).

Edited April 25, 20197 yr by phil.g00