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Single vs. three phase for heat pump, EV and appliances
Have you got your average winter production for last year, perhaps it might cheer me up.
Posted by: @david999what are you producing today, I’m only getting 0.1, overcast.
zero point one what?
percent?
kilowatts?
I can't give a straight answer to that question.
Unlike the rest of you, I have multiple arrays with different types of solar panels on them.
Some are in series, and some have series-strings in parallel.
The specified maximum output rating depends on what which array I'm looking at, and what configuration I've presently got connected using my Combiner boxes!
And I think this is straying off-topic, isn't it?
The discussion on solar output is better in your other topic on DIY solar upgrade.
'Coz I've got more information on 3-phase connections which I'm preparing to post here shortly. 😎
Save energy... recycle electrons!
Phase shift by distribution transformers
Grid transformers are designed for maximum efficiency.
To achieve this, the output frequency usually gets phase-shifted through 30°
That phase shift can be positive or negative with respect to the input frequency.
Thus different models of transformers are designated Dyn1 or Dyn11, which refers to the hours on a clock-face
The transformer on the left is Dyn1 - a positive shift of 30°
whereas the right-hand transformer is Dyn11.
This means that houses on adjacent estates are not necessarily in synchronisation with each other.
House 2 and House 3 are both identified as being connected to Phase-1, but only with reference to their local substation.
They are in fact 60° phase-shifted from each other.
For obvious safety reasons the Vector Group of a transformer is stated on its specification label.
This might be a vector-diagram, showing the order in which the primary and secondary windings are laid,
or possibly just the indication Dyn1 or Dyn11
There is no universal phase-reference in the UK.
You can't detect which phase your house is on by comparing with a central 50Hz 'clock'
Save energy... recycle electrons!
@transparent 0.1 of those mystical things that solar panels produce but evading both myself and toodles currently. However I’m in the wrong place again, must be old age.
@toodles it’s akin to growing tomatoes , big expectations, you get a few, then next minute they go and die on you. What next they get blown off the roof.
it can only get better, thats if we step up to GW. I never expected my dormer roof to blow off and need a bad winter to get confidence back that it won’t come off again. A bit of ptsd I think and my heart goes out to those folk flooded, it hurts.
Those look like solar thermal tubes.
It'll be tricky to use them on 3-phase, but you're welcome to try ! 😉️
Save energy... recycle electrons!
@transparent no they were a concept in America but went bust due to bad management. The theory was that the sun could produce electricity at any angle, were not affected by wind and so on, similar to the thermal evacuated tubes. Was researching them and its a bit of a mixed bag, interesting in terms of the similarity of the thermal tubes and how as they claimed they would work at any angle but the wave length, if I can call it that would bounce off/deflect off the curvature of the tube. White roof was the ideal and my solar thermal came with reflectors that all fell off under the tubes. Interesting I guess but they were not as efficient as flat panels and makes me wonder if flat panel thermal is better.
Posted by: @iancalderbank@editor I did look at 3 phase, it was painful, got quoted 10k just for the DNO piece. and that was for tapping into the phases that's only 5 metres away on the street , already going to neighbours houses. Plus whatever for electrician works on my side, which I never tried to get quoted for.
I have a 100A fuse, I have a HP that pulls 6kw in worst case , only at the peak of the HW cycle. Plus 2 EV's (7kw each to charge) plus fully electric kitchen (10kw ish all maxed) plus 3 powerwalls (15kw). that does all work fine with single phase 100A. because not all are on all the time, and the batteries are bidirectional.
With 100A I can and do pull 23kw from grid during offpeak in winter for several hours if everything is charging overnight on cheap rate and the HP is running all night also. If I had less than 100A I would struggle to "download" enough cheap rate charge if both cars needed a large chunk.
Getting batteries helps as it can protect the main fuse / grid. You can tell a powerwall what the max allowed grid is, it will slow down its rate of charge (or discharge if needed, providing there is some charge in it of course) in order to protect the grid fuse.
This is interesting, I think @transparent suggested there could be a method to get the DNO to upgrade the supply upgraded to three-phase on safety grounds. Or perhaps I misunderstood.
At the moment, I do not expect to draw more than 18kw, so my 100amp fuse gives room for growth...
I wonder if there could be efficiency gains meaningful to a consumer with an upgrade to three phase? This site seems to indicate a higher base cost.
8kW Solis S6-EH1P8K-L-PLUS hybrid inverter; G99: 8kw export; 16kWh Seplos Fogstar battery; Ohme Home Pro EV charger; 100Amp head, HA lab on mini PC
the 3 phase was free for me since I was looped with a neighbour. My Zappi can cope with 3 phase but I need to change the meter and other bits and not sure if there are much of a saving. I was told a smoother supply but not any faster or cheaper. It certainly would take a while to recover the costs of the meter and such…
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