Morning all,

With COJ and their crazy grid fees I'm looking into getting a LPG generator to cover my last few% of power usage and then thinking of disconnecting from COJ completely, what are the best 6-8kw LPG generators available locally that will allow the Victron Quattro to control and work well with it?

During summer Im currently 95% off grid, and winter 80%.

Currently running 9kw of panels, Victron Quattro and 7 Pylontech US3000C's

Getting tired of paying R5 - 8 per delivered kwh to COJ, so time to do another ROI calc once I get an idea of locally available and compatible gensc

1 hour ago, Justin_A said:

During summer Im currently 95% off grid, and winter 80%.

I can't suggest a LPG genny, maybe consider a Diesel genny instead, as an option, however, maybe you could possibly look at keeping consumption on your end in check a bit more, such, that you won't need additional power other than the solar + storage you already have...

We are fully off grid for more than 15 months now, no extension lead to the neighbour or anything like that and other than 2 or 3 occasions/days during those months everything worked out fine, power running 24/7 with usually more than 50% battery remaining by morning, assuming the batteries got to above 95% the previous evening. 30kWh battery and 4.7kWp solar with a 5kW inverter... round about 30-odd kWh consumption daily this time of year, in winter it's probably a lot closer to 20-odd kWh per day. As it is, I will add more panels and looking at doubling the battery capacity, then even those two dark cloudy days in a row, won't have any real impact on us...

Edited January 19, 20251 yr by Kalahari Meerkat

yeah that is the other option im looking at, switching up to heatpump geysers, and adding another array and one more battery should also get us completely off the grid, then perhaps a genny only for periods like this Dec

On 2025/01/19 at 6:07 AM, Justin_A said:

Morning all,

With COJ and their crazy grid fees I'm looking into getting a LPG generator to cover my last few% of power usage and then thinking of disconnecting from COJ completely, what are the best 6-8kw LPG generators available locally that will allow the Victron Quattro to control and work well with it?

During summer Im currently 95% off grid, and winter 80%.

Currently running 9kw of panels, Victron Quattro and 7 Pylontech US3000C's

Getting tired of paying R5 - 8 per delivered kwh to COJ, so time to do another ROI calc once I get an idea of locally available and compatible gensc

Wow! I just did a check. On my small monthly purchase I am paying about 6.40 per kWh, but I buy 62.something a month. If I doubled my purchase, the unit price will fall as the first R200 per month goes to the service fees. (all figures VAT inclusive).

Unless you do a hard disconnect - City removes both the cable and the meter - you are going to be liable for monthly fees. Estate Agents have been warning that a house in a suburban area with no grid connection may be difficult to sell. Even those of us who have solar like being able to fall back on the grid when we have to.

What's the cost of lpg to generate a kWh? That's the key consideration here.

For me, the biggest saver on your household bills, in Johannesburg, is to switch to prepaid. You pay more per kWh, but this is more than offset by the reduction in fees. Currently R200 including VAT. My electricity bill is reliably R400 a month, though at some point I am going to have to spend a bit more because I like some units in the bank.

3 hours ago, Justin_A said:

yeah that is the other option im looking at, switching up to heatpump geysers, and adding another array and one more battery should also get us completely off the grid, then perhaps a genny only for periods like this Dec

My heatpump is 13 years old, so it is not as efficient as the ones you get now. This morning it drew 1.4kW for 40 minutes to heat to 57 degrees. The geyser has an insulating blanket on it. The heatpump is kept on the backed up side of the inverter. It runs twice a day on the timer. We had hot water all the way through load shedding.

It may help us that we are two adult people, fixed in our ways, and so the heatpump only runs twice a day. Early in the morning off the battery, middle of the day usually off of PV. The insulation helps to keep the water at a good temperature until 9, even 10 at night. 

Mine is a Kwikot. I can just leave it to it's own devices, or I can use the built in timer as I do. When I had it put in the electricity bill started dropping. Once I got access to the timer and started using that the bill dropped some more. Now, because of it's lower consumption and greater efficiency I can run it on the backed up side of my PV system.

But you have to get it installed and that cost will be a big input into your ROI.

I'm bucking the odds now. Most manufacturers will tell you you'll get 10 years use. Kwikot think mine is the oldest or 2nd oldest still in operation in Jhb. So bank on 10 years.