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Re: Texas internet connectivity declining due to blackouts


From: Mark Tinka <mark@tinka.africa>
Date: Wed, 17 Feb 2021 20:40:09 +0200



On 2/17/21 20:04, Lady Benjamin PD Cannon wrote:

Other than financials limiting capacity, modern residential solar systems do not care a wink about what sort of load their DC is driving.  The inverters also are rated for continuous duty.

Solar can drive any load. But to support heavy loads + regular ones, you'd need a big array and a decent-sized inverter. Double or triple the array if you need to support the same demand during low irradiation days (rain, winter, e.t.c.).



If you produce more power per day than you consume, you will be fine forever, simply needing enough capacity to ride out volatility in production.

Most grid-tied solar installations will produce more power than they need, at some point. But that does not help if there is no storage and/or the grid fails.



Let me be clear: Solar systems are suitable for every type of electric load, but, if anything, */especially/* resistive loads, as those are driven most efficiently by the inverters, as opposed to inductive or other reactive loads.

I didn't say solar wasn't suitable for resistive loads. I said batteries aren't... not from a lack of ability, but a lack of capacity given the amount of energy that is required to drive resisitive loads over a given period of time (think, heating bathing water in a 200-litre water tank, with a 4kW element, in the dead of winter).



If everyone had a large enough solar system at home, let’s say covering their entire roof - we wouldn’t need generation at all except for certain industrial purposes. (which can be nuclear)   The grid could be shrunk dramatically as it would be a rarely used inter-tie.

Let's be clear, solar does not automatically infer batteries also.

When I say solar, I mean PV only. When I say solar + batteries, I mean PV + storage.

Much of user demand occurs in the evening, when the sunlight is at its lowest. No amount of solar on the roof will offer you power then, and if the grid is massively shrunk, where will your power come from? Fine, you've got a battery - how big does it have to be to support you throughout the night until the sun comes out the following morning, assuming it doesn't storm?

Mark.

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