– – –Germany now generates over 35% of its yearly electricity consumption from wind and solar sources, says the Asia Times

Over 30,000 wind turbines have been built, with a total installed capacity of nearly 60 GW.

Germany now has approximately 1.7 million solar power (photovoltaic) installations, with an installed capacity of 46 GW. This looks very impressive.

Unfortunately, most of the time the actual amount of electricity produced is only a fraction of the installed capacity. Worse, on “bad days” it can fall to nearly zero.

In 2016 for example there were 52 nights with essentially no wind blowing in the country. No Sun, no wind.

Even taking “better days” into account, the average electricity output of wind and solar energy installations in Germany amounts to only about 17% of the installed capacity.

The obvious lesson is: if you want a stable, secure electricity supply, then you will need reserve, or backup sources of electricity which can be activated on more or less short notice to fill the gaps between electricity demand and the fluctuating output from wind and solar sources.

The more wind and solar energy a nation decides to generate, the more backup capacity it will require.

On “bad days” these backup sources must be able to supply up to 100% of the nation’s electricity demand. On “good days” (or during “good hours”) the backup sources will be used less, or even turned off, so that their capacity utilization will also be poor.

Not very good economics.

Much better would be to limit wind and solar to a relative minimum, and rely instead upon controllable, non-fluctuating power sources operating with a high capacity factor, to meet the nation’s base load electricity requirements and to adjust total output in accordance with varying demand.

This corresponds to world-wide practice prior to the recent huge buildup with renewable energy.

Continued here.