ursl.github.io

Most years have 8760 hours. Below, efficiency is calculated as (yearly electrical energy produced [GWh]/installed power [GW])/8760h. This is the same as (yearly electrical energy produced [GWh])/(8760h*installed power [GW]), in case it’s not obvious.

In Switzerland (link)

electricity constitutes 26% of the energy consumption
electricity production
- 62% hydropower
- 29% nuclear power
- 9% rest (renewables and others)
the yearly electricity consumption amounts to ca 63TWh = 63000GWh.
per capita this is ca 6.5MWh, i.e. 17.8kWh/day.

Rules of thumb

Given a yearly energy production in a solar power plant, the required installation for peak power is (roughly)
```
P [W] ~ E [Wh] / 1400
```
For example: Pitztaler Gletscher 1.0e6 W ~ 1.45 e9 Wh / 1400. The factor 1400 is obviously 8760*efficiency, which can vary.
Modern solar power modules deliver about 200 W/m2.
Therefore the required solar module area is
```
A [m2] ~ P [W] / 200  
       ~ E [Wh] / 1400 / 200 
       ~ E [Wh] / 280000
       ~ E [Wh] * 3.6e-6
```
For example: Pitztaler Gletscher 5000 m2 ~ 1.45e9Wh / 200 / 1400. A second example, Grengiols Solar would require 50e12Wh * 3.6e-6 ~ 180e6 m2 of solar modules.

Wind farms in Switzerland

JUVENT

JUVENT is the largest wind farm in Switzerland, owned(?) by BKW. Since 2016 a total of (nominal) 37.2MW is operational. Over the past three years, on average ca. 82GWh were produced per year. This corresponds to an average efficiency of ca. 25%. The installed wind turbines are high-wind Vestas V112 (four turbines as of 2023) and V90 (12 turbines as of 2023). csm_Diagram_Juvent_Jahresproduktion_21_DE_44bbe86c60

CalandaWind

CalandaWind is placed very prominently next to the freeway in the Rhine valley between Trimmis and Chur. No real performance numbers are provided on their website, but summarily 3MW installed power and an average yearly electrical energy production of 4.5GWh is claimed. This corresponds to an average efficiency of ca. 17%. The installed wind turbine is a high-wind Vestas V-112-3.0MW.

bb3e44f7bc8b40efcee4e4cac0e48249

Solar plants in Switzerland and elsewhere

GondoSolar

GondoSolar is not yet installed, but the numbers may be illustrative of the current state of the art at an optimal position. With an installed peak electrical power of 18MW the yearly expected electrical energy production is 23.3 GWh. This corresponds to an efficiency of ca 15%. This performance estimate is comparable to the performance of the Pitztaler Gletscher (see below).

gondosolar_visualisierung_winter_luftaufnahme_1140_2 (Visualization of the project)

Pitztaler Gletscher

Pitztaler Gletscher is Europe’s highest solar power plant. It is installed and from the numbers specified on the installer’s webpage the installed peak electrical power is 1MW and a yearly electrical energy production is 1.45GWh. This corresponds to an efficiency of ca 16.6%, comparable to the expected performance of GondoSolar (see above).

photovoltaik-650-winterr

Baseline comparison (nuclear power plants)

KKW Goesgen is a large nuclear power plant (1GW electrical net power) that produces ca. 8000 GWh per year (link) This corresponds to an average efficiency of 91.3%.

Of course: Wind and solar power are intermittent, in contrast to nuclear power. Energy storage solutions do not (yet) provide adequate capacity.