Solar pointless without batteries

Spies

At least according to this guy!

https://vm.tiktok.com/ZMNMPJBAH/?k=1

I mean I get where he is coming from when you have really peaky generation it's tricky to use without grid draw, but it's not like you're not going to be getting something back for pushing out to the grid.

I don't understand the obsession with trying to draw as little grid energy as possible, yes you're probably having to buy in units at a higher rate than those going out, but he doesn't consider the extra expense for the luxury of doing so and the fact that when you're exporting your system is helping make the grid greener!

EcoScruples

He forgets a lot in there.
Solar still pays back quicker for most without batteries so his point isn't really very strong.

Batteries are a luxury as you say unless you are a high user and play tunes with off peak electric like a fiddlers elbow.

Expect more geniuses to pop up soon......

Merlin139

Obviously new to the Solar game and probably got an 8 kWh system on his roof. The longer you have Solar with or without batteries its all about educating yourself to make the most efficient use of the Free energy!

IMO a very poorly made video and he really had no real idea about what he was going to say. 

Why does he need so many strip lights in his garage?

Mikeyboy01443

Spies said:

At least according to this guy!

https://vm.tiktok.com/ZMNMPJBAH/?k=1

I mean I get where he is coming from when you have really peaky generation it's tricky to use without grid draw, but it's not like you're not going to be getting something back for pushing out to the grid.

I don't understand the obsession with trying to draw as little grid energy as possible, yes you're probably having to buy in units at a higher rate than those going out, but he doesn't consider the extra expense for the luxury of doing so and the fact that when you're exporting your system is helping make the grid greener!

Well i would say its common sense to NOT want to use any grid electricity?
Im a newbie to the solar game, i like doing my best at the moment to try and use little to no grid, that's the whole reason we get these systems no?
On paper i'm very 'green' with my solar, battery, BEV and air con in the house, but I'm not doing it to feel good about being green or being an eco warrior like some on here, I'm just tight and like to keep monthly costs to a minimum! 
The other thing i always see people say is the payback period, people ask me how long til it pays back... i dont care,  what other home improvements pay for themselves, yet people think it's not worth it if it takes too long to pay back?? 
I just dont understand this mentality...

Alnat1

I'm a solar newbie too and I'm with you on the payback thing. Double glazing saves you money on energy bills too but nobody asks how long until that pays for itself.

TBH I don't really try and use as much generation as possible, I just use what I need. In fact I'm still trying to cut down what we use to get myself into the habit for when the sun isn't shining in winter. When Outgoing Agile price is high I do try to keep use to a minimum between 4.30-7pm and would probably cook using the gas hob or slow cooker on those evenings. Maybe if we had an EV and a Go tariff and were paid less for export I'd change how I use the system.

The other thing I don't get is people using all their excess to heat hot water. Yes we all need some hot water but surely it's better to only heat as much as you need and not stick an extra 12kWh in the tank rather than let it go back in the grid. For me, using 3-4kWh of gas (30p max?) each morning to heat water, most of which we will use before lunch, is better than putting in 6kWh of generated solar in the afternoon that we could get paid 16p/kWh for. There's probably some maths says I'm wrong though lol. 

Reed_Richards

EcoScruples said:

Batteries are a luxury as you say ...

They also greatly add to your convenience.  You don't have to be careful about only using electricity when the sun is shining and you can cope with larger demands by using power from the PVs and power from the battery simultaneously.

Mikeyboy01443 said:
...what other home improvements pay for themselves...

Estate agents might say that certain home improvements enhance the value of your house by something similar to what they cost.  Do these count?

Alnat1 said:

The other thing I don't get is people using all their excess to heat hot water. Yes we all need some hot water but surely it's better to only heat as much as you need and not stick an extra 12kWh in the tank rather than let it go back in the grid. For me, using 3-4kWh of gas (30p max?) each morning to heat water, most of which we will use before lunch, is better than putting in 6kWh of generated solar in the afternoon that we could get paid 16p/kWh for. There's probably some maths says I'm wrong though lol. 

The maths that says you are wrong is the maths that applies to the vast majority of solar PV installations that don't get nearly as much as 16p per kWh for their exported electricity.  If you are on the old FIT scheme you are almost certainly on deemed export which means you get paid whether or not you actually use the electricity you are deemed to have exported in which case using all the excess to heat hot water is a no-brainer.  If you are paid for actual export then you are very fortunate indeed if you get 16p per kWh.  For example, Eon.next pay 3p per kWh as standard.    


  

Mikeyboy01443

at the moment i am still waiting for any export to be set up (come on octopus!) and i will be going on Agile, so yes i may prefer to export at the peak times, im not sure how much i use heating the water, i stick it on in the day if its a nice day as my battery is full by lunchtime, still waiting for second battery (come on battery supply backlog!) so at that point i am just giving away electricity...

on a day where i need hot water and its a rubbish solar day i will just put the gas water heating on for a bit - its nice having the choice i guess..

i havent worked out yet how much gas i may use to heat the water, you are probably right at about 30p - but when i can finally get paid to export i will do that, prices in my area tomorrow for example are 20-40p per kwh at peak times!

1961Nick

Anyone doing the 'should I export it or heat water with it?' calculation should take a good look at how efficient their gas boiler is when heating DHW in isolation. A good boiler will be 90% efficient but less so with short burns just to heat a cylinder. There's also all the pipework between the boiler & the cylinder to heat.. often 28mm or bigger! Taking all that into account, I'd be surprised if efficiency was any better than 70%, taking the actual cost of energy delivered from 7.3p/kWh to around 10.5p/kWh.

(I did a rough calculation of the capacity of my pipework from the boiler in the garage to the HW cylinder & back ... 24 litres. It takes 1kWh to raise the temperature of that water from 20C (ambient) to 55C.)

JKenH

1961Nick said:

Anyone doing the 'should I export it or heat water with it?' calculation should take a good look at how efficient their gas boiler is when heating DHW in isolation. A good boiler will be 90% efficient but less so with short burns just to heat a cylinder. There's also all the pipework between the boiler & the cylinder to heat.. often 28mm or bigger! Taking all that into account, I'd be surprised if efficiency was any better than 70%, taking the actual cost of energy delivered from 7.3p/kWh to around 10.5p/kWh.

(I did a rough calculation of the capacity of my pipework from the boiler in the garage to the HW cylinder & back ... 24 litres. It takes 1kWh to raise the temperature of that water from 20C (ambient) to 55C.)

That’s why I didn’t even bother with pipework to heat the hog water at the far end of the house.  I haven’t worked it out exactly but the pipe run from boiler to cylinder would be around 18m depending on the route. It’s only 3m to my other hot water tank. As I have oil (no gas) E7 was my original best option but now virtually all my hot water is heated by solar or Octopus Go Faster at 5.5p/kWh. 

Alnat1

I guess each of us does what works best for their own situation. Our house is a modern 4 bed detached with integral garage, just me and hubby mostly now. The boiler and inverter/battery set up are in the garage, hot water tank in cupboard on the landing above, maybe 3m away, and our en-suite directly behind the tank cupboard for showers and hubby's shave that use most of the hot water. For us the cost of an iBoost or similar didn't seem worth it.

With FIT it's a no brainer to use any excess to heat water, I understand that, but there are people looking at these threads for advice on installing new PV systems that won't get FIT and then the hot water issue is not so simple. 

Screwdriva

The fact that he is on tiktok should say it all. 

Batteries don't make sense but vehicle to home charging does (if you need an EV). With Outgoing Agile, ROI on a non-Chinese PV system with a £5K cost is <6 years now (and that's before the upcoming price cap hike)!