[snowwindwaves]

Large power transformers have efficiencies in the 98-99.75% range.

I don't doubt switch mode could be smaller and cheaper up to some size, but I am struggling to see transformers larger than about 5 mva being replaced with power electronics.

Solar farms etc have inverters in modules I believe 500 kva each - and of course the power electronics are necessary there, there is no substitute.

I have a 20 MVA transformer that is nearly at end of life and would be open to cheaper replacements.

[mschuster91]

> but I am struggling to see transformers larger than about 5 mva being replaced with power electronics.

We already see these at the substations at each end of a HVDC link, China is operating well over a dozen of them with capacities of up to 12 GW (https://en.wikipedia.org/wiki/Ultra-high-voltage_electricity...).

[hwillis]

For 5-20 MVA you're talking about 67 kV substations or similar, where a transformer costs in the low 6 figures. HVDC converter stations in the same range would cost somewhere around 8 figures, although that's mostly a guess- you typically need maintenance and supervision in a way that you don't with transformers. 1%+ downtime is pretty common, which absolutely sucks if you aren't a full grid and can't pull extra generation.

[mschuster91]

Yeah, but that price tag is mostly due to the fact that HVDC isn't a widespread technology yet. Once factors of scale come into play, the situation will look different and the prices come down.

Additionally, the price of copper is already at an/near the all-time high and it's not going to get cheaper, and the land on which huge transformers sit is shooting up in value... so in the end, market forces may push towards solid-state technology anyway.