Hi, everybody I am new here
I’ve skimmed some surface of this subforum and am still continuing to do so and still will and I’d be grateful even for google keywords for further reading
… but here is an idea that kinda appeared / dawned on me:
I have recently acquired the OpenEVSE wallbox (and had it professionally installed, with new extra switch and paraphernalia) - although as in the part of the country where I’m at, the EVSE of the most visible charging point operator is (free when available) but I got the wallbox anyway as this will not be the case forever. Anyway that’s not the point of this post so pls read on.
I am eyeing on adding a Solar PV installation to my home kinda… gradually, possibly in £1000-£2000 portions at a time.
My roof(s) I plan on adding that on, are East-West (I am on a northern half of a semi-detached building so no access to a south facing anything…)
I have a 0.9/1 storey-ish high ‘garage’ (or more like, metal shed) to which I could add the PV panels myself, without asking for assistance of any roofers (the main house is 2 storey, with concrete roofing ‘shingles’) with really awkward access from the ground, requiring awkwardly positioned ladders or a cherrypicker to do anything there. So I’d rather delay adding any substantial work to the main house until the ‘pilot plant’ on the garage ‘proves’ itself…
( just to provide the sunshine context, in december last year I only had 34 hours of sunshine in this COUNTRY… but that can rise to 74h around March and 250+ in April/May - generally stays above 70h per month Apr-Aug - per statista.com, but yeah I am at ~54-55 deg lat north; also it starts to get enough sunshine to see things ~4AM in May-June, and stays lit until ~10pm, vs 8AM to 4PM in December… ).
Apart from the EVSE unit i also have only pretty small (standard, I believe, 200-250l maybe?) UK Standard hot water tank available (original heating installation in the house is OFCH, and for now, I need to keep it…) with just one electric heater ‘booster’ up top. Not much chance changing that for something else too soon either.
Having these in mind here is what I am thinking about:
initial installation : 2 to 4 200-400W panels, (1-2 per side of roof) with grid-tied microinverters, on the garage/shed
there are e.g. Y&H solar microinverters (available e.g. on Amzn or Eb*y) that don’t seem to be interfacing with any sort of monitoring system, wired or wireless - but this is actually a good thing for this idea, please read on -(apart from, the price being substantially less than £100 per unit) so I’d match these to some cheap/available PV panels;
use emontx to monitor grid supply and pv (for a type 2 install) at the main ‘consumer unit’ fuse box (the below emonpi or base hub station being actually in the garage)
use the MQTT relay per panel WiFi MQTT Relay / Thermostat - Shop | OpenEnergyMonitor (it’s kinda expensive, so on second thought, maybe rather slap-add a 4-8 relay board to emonpi?) to control the inverters on or off - using emonPi Energy Monitor - Solar PV Bundle - Shop | OpenEnergyMonitor (sorry could not link the second link with being a beginner…) as the starting point
with emonpi/emoncms programming on the pv-bundle, interact to the OpenEVSE and the hot water heater such that, if the car isn’t connected, or its battery is full, and the tank heater isn’t taking power when it’s thermostat trips at e.g. 65-70 deg (i tend to like to keep my hot water hot), I do not export anything out to the grid. I won’t be going off-grid with this system
and if i can’t sink the pv energy in the house altogether, use the relays of whatever kind i end up using, to just.switch.the.panels.off when not needed…
Hopefully the above makes sense
Kind Regards from first-time-poster