Solar seems pretty much a given for us. We have a bunch of roof space, a bunch of yard space, a clear Cantabrian sky, some darn sexy azimuths, and 3-phase from the grid just begging to be quarrelled with by the sun.
But what about batteries? What about early adoption of wind?
We've got a bunch of quotes from a bunch of reputable companies recommended by the good geeks on other threads here. I won't name them now but I'll follow up with our final opinions once we've made a decision.
The problem is they've each come at this from a wildly differing perspective, and their advice contradicts one another.
Going in we know this:
- we're not concerned about power outages
- we are currently home during the day, with a live-in elderly couple with their own living area and cooking facilities
- we run air con all day to balance the temperature for our infant kids
- our power usage is unsurprisingly high right now ($25 per day)
- we use 2 of our 3 phases currently
- wind average here is 5.79m/s
- roof pitch 32deg, room for 23 panels facing NW, 11 facing NE
- with Electric Kiwi, could shift to MoveMaster plan for best buyback and halved night rate, or Meridian (17c buyback)
- all of these installers offer to divert juice to our hot water before sending it back to the grid
- we don't have an EV and likely won't buy one for 3-6 years
They say: "There's no way you can get 38 panels there without some hanging over the edge or in a dumb place. There's no point having 15+kW of juice if your inverter totals 11 or less."
We think: They may have forgotten we have more than one phase. They're able to install soonest which is tempting.
They say: "Our inverters each have an up to 3kW PV outlet which you can plug things into during the day in case of a power cut.
We think: They've suggested 4 panels on the SW face - this seems dumb except quite a bit of evening sun blazes from that direction and neighbours have panels on this face. They claim great quality inverters and panels but promoted this by repeatedly slagging the other products as "cheap, Chinese, fake 25 year warranty". It was a bit of a Sinophobic sales pitch.
They say: "We're confident in our panel layout and have never had to change things once we come on site. Batteries generally aren't worth it."
We think: Big diff between system capacity and inverter capacity. Only installer not to come for a site visit.
They say: "To get to this capacity we'd need to install as a ground array. We don't do systems without a battery as we recommend efficiency over a 24h cycle. We'd estimate 60kWh from wind in winter. Our wind turbines are silent."
We think: Ground array doesn't appeal. Wind does. Good capacity matching across the components. Bloody expensive.
Advice warmly appreciated because the contradictions are many.
- Is it worth maxing out the system if it'll zero our power bills?
- Is it a recommended thing to have inverter and battery capacity as >90% of system capacity?
- Are batteries overkill unless worried about self-sufficiency?
- Is wind still a foolish investment or is it worth taking seriously?
- Are SW facing panels really a silly idea given evening sun?
Any insights/experiences appreciated.