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Admiral_Fancypants t1_ixcwgso wrote

I thought the whole reason we use alternating current is because direct current can't be transmitted over long distances.

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manual_tranny OP t1_ixcx634 wrote

It is very much the opposite.

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Admiral_Fancypants t1_ixcyqjv wrote

That's news to me. Glad to hear that our 100 year old grid can be improved upon.

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VitaminPb t1_ixd9yq9 wrote

If you read it, they need buried lengths of 50-95 KM cable (big slop factor there, non trivial task to dig) to break even, and about 800+KM runs for non-buried cables. Those are very long cable runs.

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danielv123 t1_ixdxq0o wrote

Yep. The reason we have AC instead of DC on the grid is because semiconductors wasn't a thing when the grid started, which meant there was no good replacement for transformers.

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SentientHotdogWater t1_iy0nmlq wrote

Our grid isn't actually 100 years old. It's been getting continuously rebuilt and upgraded this entire time.

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NH_Living_Free t1_ixdtwod wrote

The biggest thing standing in the way is politics. Texas, as one example, is on its own grid, which has failed several times over the past three years alone in both hot and cold weather. This map shows Texas connected to the same grid, which I don’t see as politically feasible. Remember, they still re-elected Greg Abbott.

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jerzy4 t1_ixd0gtg wrote

Dc can be transmitted any distance but is only more efficient over ac in the very long distance range (with appropriate infrastructure = $$$). Our current grid uses ac as there are less losses to do so (arguably in certain areas) due to the smaller length of transmission.

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Admiral_Fancypants t1_ixd0v2z wrote

I just remeber hearing about Edison's terrible DC lines that couldn't go more than a couple miles before losing strength and needing to have substations to keep it going.

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glambx t1_ixd8xdx wrote

The issue was they didn't have semiconductors that could produce high voltage DC.

Transformers were easy to build, so achieving high voltage AC was a piece of cake.

At a given power level, line losses are inversely proportional to line voltage.

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jerzy4 t1_ixd39dd wrote

I do too. If I remember correctly hearing that his experiment was trying to balance and send out 110v across the wires only a few miles.

But if he produced high voltage and ran his wires over 100 miles he might have shown how the losses are indeed less than ac in the same setup. Our cable technology is very different from back then too

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