Not sure if I see the point of this.
The key issue for me is whether the pricing is rising or falling. So for example if the price now is 13p and in the next slot is 18p, I want to charge my battery. If the price in the next slot is 13p or lower, I don’t want to charge.
The other factor is whether the import price is lower than the export price, which for me is currently 15p.
Arbitrary colour coding doesn’t help either of these.
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