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European Super Grid

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Re: European Super Grid

#31

Post by Reason077 »

Diggsey wrote: post #15
Reason077 wrote: post #10

Earlier quoted context omitted.

Solar thermal is more efficient than photovoltaics in terms of energy captured per unit of surface/land area. However, photovoltaics are significantly cheaper per unit of energy generated. So, solar thermal makes more sense in space-constrained environments rather than vast deserts. Solar thermal also makes more sense where you're directly utilising the heat generated, eg: for industrial processes. If you're just usi…

AIUI, photovoltaics also lose a lot of efficiency when they heat up, so the ideal place to use them is somewhere cool but with a lot of sun. In contrast, solar thermal runs at extremely high temperatures to begin with, so even in a hot climate, there's a huge temperature difference from which to extract power. It seems to me that mirrors would be cheaper than photovoltaics, and the power-plant itself is a fixed cost,…

Yes, the ongoing maintenance costs associated with turbines are significant. Lots of moving parts, high temperatures, high pressures, etc. Photovoltaics, on the other hand, are very low maintenance.

There's also a nice scalability aspect to PV: if you want to expand your plant's output, it's really just a matter of adding more panels as you need them. Where as once you hit the limits of your collector/turbine/etc, you pretty much need to build a whole new plant to expand it further.

One of the world's largest solar farms is in Dubai, obviously an extremely hot region. It contains a mix of PV and thermal technologies, though it sounds like they are leaning towards more PV for future phases:

https://en.wikipedia.org/wiki/Mohammed_bin_Rashid_Al_Maktoum...

Re: European Super Grid

#32

Post by JoeAltmaier »

Reason077 wrote: post #31
Diggsey wrote: post #15

Earlier quoted context omitted.

AIUI, photovoltaics also lose a lot of efficiency when they heat up, so the ideal place to use them is somewhere cool but with a lot of sun. In contrast, solar thermal runs at extremely high temperatures to begin with, so even in a hot climate, there's a huge temperature difference from which to extract power. It seems to me that mirrors would be cheaper than photovoltaics, and the power-plant itself is a fixed cost,…

Yes, the ongoing maintenance costs associated with turbines are significant. Lots of moving parts, high temperatures, high pressures, etc. Photovoltaics, on the other hand, are very low maintenance. There's also a nice scalability aspect to PV: if you want to expand your plant's output, it's really just a matter of adding more panels as you need them. Where as once you hit the limits of your collector/turbine/etc, yo…

Their O&M is higher than the 'capacity' figures make it seem. They run under 25% capacity on average.

This site https://www.scottmadden.com/insight/solar-photovoltaic-plant... estimates $60 per kW-year for maintenance. Half cleaning; most of the rest in inverter replacement. How does that compare with turbine I wonder.

Re: European Super Grid

#33

Post by Reason077 »

JoeAltmaier wrote: post #32
Reason077 wrote: post #31

Earlier quoted context omitted.

Yes, the ongoing maintenance costs associated with turbines are significant. Lots of moving parts, high temperatures, high pressures, etc. Photovoltaics, on the other hand, are very low maintenance. There's also a nice scalability aspect to PV: if you want to expand your plant's output, it's really just a matter of adding more panels as you need them. Where as once you hit the limits of your collector/turbine/etc, yo…

Their O&M is higher than the 'capacity' figures make it seem. They run under 25% capacity on average. This site https://www.scottmadden.com/insight/solar-photovoltaic-plant... estimates $60 per kW-year for maintenance. Half cleaning; most of the rest in inverter replacement. How does that compare with turbine I wonder.

This is from 2010 so I'd imagine the figures have likely changed significantly since then, along with all the economics of photovoltaics. Today's inverters are almost certainly more reliable than pre-2010 models.

Cleaning is certainly a cost in dry areas where dust can coat the panels. But generally not in temperate climates where you can rely on self-cleaning via regular rainfall.

Re: European Super Grid

#34

Post by pedrocr »

the8472 wrote: post #24
pedrocr wrote: post #16

Earlier quoted context omitted.

Hydro and wind have the opposite seasonal variability to solar. And since some hydro allows shifting energy during the day even in summer it may be enough for a mix that solves both seasonal and daily/weekly variability. Build enough wind and solar to cover the total energy needs evenly during the year and use those 6+ days of hydro to shift energy during the day/week to solve the unreliability. Maybe 6 days of hydro…

> Hydro and wind have the opposite seasonal variability to solar. There isn't much growth potential for hydro since it's more dependent on geography than the others and many sites are already occupied. Short of mega-projects trying to exploit ocean currents. > Build enough wind and solar to cover the total energy needs evenly during the year That means you need to overbuild PV and wind independently, which may be an…

> There isn't much growth potential for hydro

But there's significant potential in wind, particularly offshore.

> That means you need to overbuild PV and wind independently, which may be an option but a costly one.

Quite the opposite. Exactly because wind and solar have opposite seasonality you need to overbuild less in total with the sum of both than you would independently. See the spreadsheet. The 100% renewable scenario only requires 15% overbuild in total and it's all in solar which is now the cheapest electricity source ever. It also maintains net exports to the rest of Europe over winter which is probably when those exports are most valuable.

> And you'd still need more storage, 6 days are too short, there are lulls that last longer than that.

Even when in a "lull" the sources aren't at 0. 6 days of full load fills gaps much larger than 6 days.

> If seasonal storage can be built then it would complement both sources and could decrease the required overbuild factor.

It would have to be very cheap to be competitive with only 15% of overbuild, particularly of solar. I don't think any of the existing or proposed technologies come even close.

Re: European Super Grid

#35

Post by LargoLasskhyfv »

throw0101a wrote: post #27
jopsen wrote: post #19

Earlier quoted context omitted.

[3] makes me wonder if we could simply convert Iceland to a giant geothermal power plant, and power most of Europe.. Sure, it would take some investment, but isn't the technology already here?

That'd be quite the underwater cable. It'd span about 900 km to get to the Scottish mainland: * http://www.gcmap.com/mapui?MP=r&R=900km%40BIHN 1050 km to reach the tip of Norway (or Ireland).

So what? Use the https://en.wikipedia.org/wiki/Faroe_Islands as junction, and branch from there to Scotland and Norway.

Each branch wouldn't be that different in distance from the part between Cyprus and Crete from the https://en.wikipedia.org/wiki/EuroAsia_Interconnector or the related https://en.wikipedia.org/wiki/EuroAfrica_Interconnector

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