Geyser timer solution for solar

[Splinter]

This!
A heat pump is nice, but then it's only good for water, upgarde the solar and it's good for everything.
I am 99% off grid, for my needs at least there's no way i'd spend 50k on a heat pump instead of another battery + panels.

This is a good point - but really only applicable when you already have solar I reckon.

If you are starting from ground zero, it might be more cost efficient to go for a heat pump?

 

[Speedster]

This is a good point - but really only applicable when you already have solar I reckon.

If you are starting from ground zero, it might be more cost efficient to go for a heat pump?

The question is whether solar is in the mix at all, or not. Whether you're starting from scratch, or adding later, it'll almost always be better going bigger on solar than adding a heat pump

 

[isie]

This is a good point - but really only applicable when you already have solar I reckon.

If you are starting from ground zero, it might be more cost efficient to go for a heat pump?

no its more relevant if you starting from scratch I would invest that cost in more panels and or batteries as again its not just used for water.
after you already have solar and got extra to spare then you can start looking at a heat pump*
even then though if i add more panels and batteries i probably wont change the geyser to a heat pump ill probably up the element to 4kw just to heat water insanely faster.

 

[PsyWulf]

At a friend of mine's I installed an ATS in the DB to switch to Grid if Solar is "unavailable",and a Tuya Smart breaker that can be scheduled on/off,manually triggered or added in HA with some logic to only enable Solar-feed to the ATS if certain conditions are met so if that Switch is On the ATS switches over to feed from the Solar system

 

[Splinter]

The question is whether solar is in the mix at all, or not. Whether you're starting from scratch, or adding later, it'll almost always be better going bigger on solar than adding a heat pump

Hey, I'm a solar person. Just thinking out loud if you only had R50k to spend. Because if solar is always the best option, then why do heat pumps exist

 

[Splinter]

no its more relevant if you starting from scratch I would invest that cost in more panels and or batteries as again its not just used for water.
after you already have solar and got extra to spare then you can start looking at a heat pump*
even then though if i add more panels and batteries i probably wont change the geyser to a heat pump ill probably up the element to 4kw just to heat water insanely faster.

I'm talking about a limited budget of say R50k.

As per my previous post, I'm a fan of solar, but just spit-balling as to whether there is any scenario where a heat pump is the better option.

 

[denmendez65]

The question is whether solar is in the mix at all, or not. Whether you're starting from scratch, or adding later, it'll almost always be better going bigger on solar than adding a heat pump

Yeah but Lupus did spend 25k on his. 50k is a bit steep. To try and build a solar system to math the Heatpump savings might not be worthwhile. Remember when the rain and clouds hit, your big system wont produce much. So efficiency wins which is a what a heatpump does well.

 

[Lupus]

Hey, I'm a solar person. Just thinking out loud if you only had R50k to spend. Because if solar is always the best option, then why do heat pumps exist

You also eventually run out of space to put panels . Though 50k seems a lot for a heat pump

 

[Speedster]

Hey, I'm a solar person. Just thinking out loud if you only had R50k to spend. Because if solar is always the best option, then why do heat pumps exist

Because in larger parts of the world solar isn't an option (and hasn't been historically). Heat pumps are far superior than elements for heating water, but they're not cost effective. You will get much more bang for buck from extra panels than from installing a heat pump (assuming space for panels).

If someone gave me R50k to improve my energy efficiency, heat pump wouldn't be high up on the list. If someone gave me a heat pump I'd gladly install it.

 

[denmendez65]

You also eventually run out of space to put panels . Though 50k seems a lot for a heat pump

And there is that. Needs to be a balance of efficiency vs sizing the PV system.

 

[isie]

I'm talking about a limited budget of say R50k.

As per my previous post, I'm a fan of solar, but just spit-balling as to whether there is any scenario where a heat pump is the better option.

if you not even thinking about putting Solar and just looking at cutting electrical cost then heat pump at 50k budget though you could probably retrofit a Solar geyser and Heat pump and cut your electrical cost significantly

 

[Lupus]

Yeah but Lupus did spend 25k on his. 50k is a bit steep. To try and build a solar system to math the Heatpump savings might not be worthwhile. Remember when the rain and clouds hit, your big system wont produce much. So efficiency wins which is a what a heatpump does well.

Yup throughout the rainy bits where we've had kak generation the heat pump has run from 6am to 10pm without issues and we've had hot water 99% of the time, the only time we didn't is when it's trying to heat water after a bath but I mean that's normal and it's generally done in 45 minutes top.

 

[Speedster]

Yeah but Lupus did spend 25k on his. 50k is a bit steep. To try and build a solar system to math the Heatpump savings might not be worthwhile. Remember when the rain and clouds hit, your big system wont produce much. So efficiency wins which is a what a heatpump does well.

Even at R25k panels would win. For that price you can get upwards of 6 kWp, which will give you 15kwh on a bad day, 30kwh on a good day. Even the 15kwh is more than enough to heat your water with plenty to spare for other use.

 

[Splinter]

You also eventually run out of space to put panels . Though 50k seems a lot for a heat pump

Fortunately I have plenty of space

Got 14 panels at the moment, and want to put up more for them pesky winter months.

 

[Lupus]

Even at R25k panels would win. For that price you can get upwards of 6 kWp, which will give you 15kwh on a bad day, 30kwh on a good day. Even the 15kwh is more than enough to heat your water with plenty to spare for other use.

Shoo don't know if you know how dark JHB can get in summer storms I've seen mine drop to 200w with a 9.2kw on my roof, when I had just 4.3 it was down to 50.

 

[denmendez65]

Even at R25k panels would win. For that price you can get upwards of 6 kWp, which will give you 15kwh on a bad day, 30kwh on a good day. Even the 15kwh is more than enough to heat your water with plenty to spare for other use.

Guys on here with 9 to 10kWp of panels struggled to hit 15kWh just a few weeks ago. Throw in family of 5 with a geyser consumption of 10kWh a day and you only have 5 left for the house. With a HP it would be 3kWh for the geyser and 12 left for the house and battery.

Production drops a ton in bad weather.

 

[Lupus]

Fortunately I have plenty of space

Got 14 panels at the moment, and want to put up more for them pesky winter months.

Got 16 panels, I could put up more, but the shade on one part of the house is persistent for quite some time. JHB parks aren't known for trimming trees or doing maintenance. But even if I added another 8 for 25k they'd still not be as efficient during cloudy weather as the heat pump, it might push me up to 400w meager generation

 

[Lupus]

Guys on here with 9 to 10kWp of panels struggled to hit 15kWh just a few weeks ago. Throw in family of 5 with a geyser consumption of 10kWh a day and you only have 5 left for the house. With a HP it would be 3kWh for the geyser and 12 left for the house and battery.

Production drops a ton in bad weather.

I have 9.2 and 15 was a struggle, can't check my history for last month as solar assistant crashed, but I think some days I even had 11

 

[denmendez65]

Fortunately I have plenty of space

Got 14 panels at the moment, and want to put up more for them pesky winter months.

Yeah, for my situation I still have the whole house roof, my 6.5kWp of panels is on the garage roofs. So in my case I would get more panels for 25k. But i think most dont have that luxury so they have to focus on efficiency, especially with water heating. Which is where a Heat pump wins hands down.

Unless you put 10 geysers in series

 

[Lupus]

Yeah, for my situation I still have the whole house roof, my 6.5kWp of panels is on the garage roofs. So in my case I would get more panels for 25k. But i think most dont have that luxury so they have to focus on efficiency, especially with water heating. Which is where a Heat pump wins hands down.

Unless you put 10 geysers in series

Also our winter months are pretty good, though early Spring is better it's just Summer and early Autumn that really sucks.