If I did not know better.

[DavidFrancis]

Thanks for the replies @pdf27 and @TerryE 

I guess I was being thick, but the design of that graphic made it look like the losses came after the energy had already departed the power stations and I was thinking the conversion losses happened when changing voltages or going from AC to DC or vv.

 

One of the accompanying tables to the DUKES report gives fuel-used to electricity-generated figures by fuel type and these give the following efficencies:

Coal 33.4%

Oil 36.5%

Gas 48.5%

Nuclear 39.9%

Thermal renewables 36.9%

 

Solar & wind are given as 100% 

[SteamyTea]

20 minutes ago, DavidFrancis said:

losses came after the energy had already departed the power stations and I was thinking the conversion losses happened when changing voltages or going from AC to DC or vv.

Why the terms Primary Energy and Delivered or Consumed Energy are often used.  If emissions are being calculated, then Primary energy is usually used.  At a household level, then Delivered Energy is usually used. though I think Passivhaus may use Primary Energy.

20 minutes ago, DavidFrancis said:

Solar & wind are given as 100% 

I am surprised, but that may be for two reasons.  They tended to be close to the consumer, so only very small transmission losses.  Not so much the case now for larger PV and Wind farms.

The other thing is that as the fuel source is renewable, efficiency becomes a physics question, not a practical one.

Both Wind and silicon PV have about reached there practical efficiencies, though PV may get another few percent, but not really a material difference.  People get excited about dual layer PV, but that, in a physical properties context, is really 2 modules, one on the other, and neither has the conversion factor of a single module (yet, may be surprised).

If you look at PVGIS, they have whole system efficiency losses, default is 14%.  I am not sure if that is based on the raw data i.e. a 1 kW_p 20% efficiency loss system will deliver 0.8 kW during standard testing, at the wall socket, or it is from collected system data and averaged out.

Edited January 9, 2023 by SteamyTea
Tried to better explain PV losses.

[saveasteading]

3 hours ago, SteamyTea said:

tended to be close to the consumer, so only very small transmission losses

On a plane landing at Copenhagen several years ago, I could see the turbines scattered throughout farmland, rather than in clusters. Plus the big wind-farms out at sea. I believe they also have relatively small farm waste to power, stations, also scattered around the grid.

[pdf27]

3 hours ago, SteamyTea said:

Why the terms Primary Energy and Delivered or Consumed Energy are often used.  If emissions are being calculated, then Primary energy is usually used.  At a household level, then Delivered Energy is usually used. though I think Passivhaus may use Primary Energy.

It used to use primary energy, nowadays it uses "Primary Energy Renewable" which is complex but not horrific if everything is electrified. If you're burning anything it's really hard to figure out what they're asking for - I think the assume e-fuels, but it isn't at all clear.

[SteamyTea]

1 hour ago, saveasteading said:

could see the turbines scattered throughout farmland, rather than in clusters

Different finance model and land ownership maybe.

I think they have more community ownership of RE in Denmark.

Also wind turbines work better when spaced far apart.

25 minutes ago, pdf27 said:

If you're burning anything it's really hard to figure out what they're asking for

Yes. Burning anything makes it harder to calculate.

[saveasteading]