Dabbling with solar and batteries

MP1995

Martyn1981 said:

Sorry, didn't make the obvious connection, Doh! Looks like you have decent options, but connecting them to the grid (for discharge) is where all the rules and regs kick in.

Tumble dryer is a great use. You mention an air/con unit, is a heat pump? Several of us use A2A units to help heat the house from spare PV during the Spring and Autumn. So that was my first go to, for a 'mains' device that could run off batts.

I don't know much about electrickery, but am I righ to think micro-waves and induction hobs are more difficult as they pulse demand?

I'm really quite fascinated with your plans, just should have read it a bit slower, and more carefully.  

PS - very (very) envious of your £600 deal. 

Yes we have an A2A heatpump wall hung everythingnin the box unit in the garage converted gym which provides heat in the winter very efficiently and cold in the summer even more efficiently.

I am just playing about as it's a sunny afternoon with running the panels in series or parallel.

It does make me smile that solar is charging one as 600w and the other is cooling the gym to 18oC for 500w.



The excitement of my first taste of free (except the outlay) energy since my casino calculator lol.

We are considering A2Amulti split system for the house (we have a heatpump already) mainly for cooling but also for those times when you don't want to be running the heatpump 24/7for heat just before the colder months appear and just as they finish. Howeverthat depends on whether we move or extend in the near future and that will then mean a proper solar/battery install bother professionals.

Lots of ideas just haven't connected the dots yet and will have a chat with my neighbour electricians for their opinions,

MP1995

To add we regularly use two portable induction hobs on the ecoflows with no issues one peaks at 2100w and the other just under 2000w which is fine as the ecoflow can handle a spike up to 3000w

diveleader

I think you should stay non grid tied and just island units connected to your system.

Look at how you can connect more loads to the Ecoflow units, so you can reduce your grid draw.
Fridges / freezers could be a good shout? (my freezer uses approx 1kWhr per day)

Charge with solar when available and off peak during the winter

You would need to consider how you would be alerted, should the Ecoflow units shutdown due to low battery

MP1995

diveleader said:

I think you should stay non grid tied and just island units connected to your system.

Look at how you can connect more loads to the Ecoflow units, so you can reduce your grid draw.
Fridges / freezers could be a good shout? (my freezer uses approx 1kWhr per day)

Charge with solar when available and off peak during the winter

You would need to consider how you would be alerted, should the Ecoflow units shutdown due to low battery

Thatis definitely plan A, was just considering what it might take to add to the house and if any others here had connected their home brew to their house.

I had just 3 250w panels connected yesterday which was not the best if sunny daysand harnessed about 2.5kwh which meant the tumble dryer and air con for the gym and all gym electrics was free.

So far today we have harnessed 1.4kw from 3 of the panels, again a cloudy day but thr ecoflows are 92% and 80% full with a tumble dryer load going on in half an hour.

It's all fun at the moment and at leat I know even on the east facing outbuilding roof good solar generation is possible.

Solarchaser

I still recall my first foray into solar, and it's taken me on a bit of a journey if truth be told.

The other forum users are warning you about legalities etc and they are probably right to do so, as you could cause yourself problems.

I'm a little less risk averse I guess.
I have one array which was installed by a proper installer and one which is diy.

Your panels, I like to think about them as DC batteries. 
So if you're inverter likes 60v more than 30v then you should probably put 2 in series to up the voltage.
But if it prefers 25v instead of 60v, then they should probably go in parallel. 

The inverter should tell you it's start up voltage and it's maximum voltage.
You ideally want to be fairly close to the maximum to get the best efficiency out of your inverter, but that is inverter dependent and you should search t'internet for the efficiency curve of your inverter to see what will suit best.

I would advise seeking advice from a spark before connecting to the grid.
Cards on the table, I didn't, as I'm fairly confident (though maybe not competent) with electrics.
But it's always good to get advice from someone you trust, and that has knowledge you are lacking.

Qyburn

MP1995 said:

Thatis definitely plan A, was just considering what it might take to add to the house and if any others here had connected their home brew to their house.

It's as good as certain that you can't (shouldn't) connect the Ecoflow output to the house at the same time as the grid supply. Specific grid-tied inverters detect the existing supply and adapt their output to comply, voltage, frequency and phase. Connecting the Ecoflow will act as if it and the grid are shorting each other out, a contest that the Ecoflow will probably lose. 

MP1995

Qyburn said:

MP1995 said:

Thatis definitely plan A, was just considering what it might take to add to the house and if any others here had connected their home brew to their house.

It's as good as certain that you can't (shouldn't) connect the Ecoflow output to the house at the same time as the grid supply. Specific grid-tied inverters detect the existing supply and adapt their output to comply, voltage, frequency and phase. Connecting the Ecoflow will act as if it and the grid are shorting each other out, a contest that the Ecoflow will probably lose. 

If you read the thread  I would not connect the ecoflow it would be an electrician connecting an inverter to my garage consumer unit and I woukd connect my homebrew from there.

Qyburn

MP1995 said:

Qyburn said:

MP1995 said:

Thatis definitely plan A, was just considering what it might take to add to the house and if any others here had connected their home brew to their house.

It's as good as certain that you can't (shouldn't) connect the Ecoflow output to the house at the same time as the grid supply. Specific grid-tied inverters detect the existing supply and adapt their output to comply, voltage, frequency and phase. Connecting the Ecoflow will act as if it and the grid are shorting each other out, a contest that the Ecoflow will probably lose. 

If you read the thread

Thanks. I did read the thread but it wasn't clear whether you are or aren't expecting to incorporate the Ecoflow units into the final rig.

Are you planning just to retain the solar panels, and connect them to a grid tied inverter instead of to the Ecoflows?  If so and assuming the capacity doesn’t exceed 3.68kW (strictly 16A), and the new inverter is type approved, then that could be declared to the DNO to keep everything legal.

Reed_Richards

Qyburn said:

MP1995 said:

Qyburn said:

MP1995 said:

Thatis definitely plan A, was just considering what it might take to add to the house and if any others here had connected their home brew to their house.

It's as good as certain that you can't (shouldn't) connect the Ecoflow output to the house at the same time as the grid supply. Specific grid-tied inverters detect the existing supply and adapt their output to comply, voltage, frequency and phase. Connecting the Ecoflow will act as if it and the grid are shorting each other out, a contest that the Ecoflow will probably lose. 

If you read the thread

Thanks. I did read the thread but it wasn't clear whether you are or aren't expecting to incorporate the Ecoflow units into the final rig.

Are you planning just to retain the solar panels, and connect them to a grid tied inverter instead of to the Ecoflows?  If so and assuming the capacity doesn’t exceed 3.68kW (strictly 16A), and the new inverter is type approved, then that could be declared to the DNO to keep everything legal.

"... could be declared to the DNO ..."?  Or should be declared?  Or must be declared?  I think the answer is "must"; but I could be wrong.

Qyburn

"Must" to be legal.