Winter is coming

(I know, I know and I’m sorry.  But couldn’t help the GoT reference…and neither can the other thousand journos writing about anything to do with our approaching cold months.)

I’m often asked what happens at our place during winter.  The answer is simple – pretty much the same as what happens during summer.

Solar panels need light, not heat.  Therefore, as long as we get some sunlight throughout the day the battery bank will float (reach 100% state of charge).  I’ve often been surprised by just how efficient the panels are at harvesting power to top up the battery bank.

What does change slightly during a Melbourne winter, is I check the weather report each day.  Here’s what popped up today.

Melbourne's weather this week

Melbourne’s weather this week

While a run of those little grey cloud symbols is slightly disconcerting, with very little power being pulled in the house during the day, the chances are there’s enough light around for the battery bank to float.

But what if there’s not?

a) the battery will have a lower state of charge (SOC), usually around 95-97% until the next sunny day.

b) we could connect a back-up generator that would float the batteries – while our system is set up to connect a gennie, we haven’t done so because we’ve never been low enough to warrant the $7k purchase cost.

I think that running out of power is a concern for people thinking about going off-grid (it was for me when we started this process a few years ago).  However, in two and a half years and coming into our third Melbourne winter, we’ve never been lower than 92% SOC.

As we enter this cloudy week, I’m planning to keep a record of SOC…watch this space!

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One thought on “Winter is coming

  1. Should be interesting observations. When we came to the open day we had been waiting 4 mths for installation but now we have 20 panels up top. We too have been surprised by how much is generated on seemingly overcast days.

    Cheers Lynda

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