Canadian Politics Today

It generates 7.1% of its power from solar even if 30% of the installed capacity is solar. The difference in the two numbers illustrates how inefficient solar is and how much Germany depends on the non-renewable dispatchable power sources.

I meant to say over a third (36%) by renewables, of which solar is a major component.

About 1kw of solar energy reaches the Earth surface per square meter. That is a lot of energy. If the average home consumes about 10kwh per day, then you need 10 hours for a square meter or 10 square meters (size of a garden shed) for 1 hour of sunlight. Today's solar panels are only about 25% efficient so you need about 4 times that amount.

Except 1KW of incident radiation is only available for panels mounted on racks that follow the sun. Fixed solar panels don't get anywhere new that amount of energy for 10 hours a day. Maybe 2-3 hours tops. Moreover, any cloud cover reduces the available energy so unless you live in a desert a lot of days there will be less than 1KW even at peak times. Lastly, people don't stop using power when the sun goes down and they need electricity so it makes no difference if solar panels were 100% efficient and as cheap as paper, they would still be an expensive source of energy. The only thing that will change the poor economics of solar will be cheap batteries but we are a long way from that.

In So Cal there are some huge wind farms in the Mojave area and between Riverside and Palm Springs. The other day we drove through Mojave in a calm and not one of them was turning.

How does it do that during the winter when there is less than 8 hrs of daylight at 50N and for much of it the sun is fairly close to the horizon?

Well of course  solar power has it's limits especially based on where you live. When the sun goes low in Germany, they have wind farms which can pick up the slack. Then they have hydro and nuclear. Point being is they now produce a little over a third of their power from renewables. They fell behind somewhat due to political events more so than scientific events and China is now kicking their butts, especially in the manufacturing sector-you want a solar panel to stick on your roof in Germany you have to order it from China. I have walked the streets in various Scottish towns when there were thermal inversions in winter and it certainly convinced me we need to leave that coal **** in the ground, cough, cough.

waldo factoid: many of those turbines, particularly the initial/early 80s vintage, have been shuttered. In some cases waiting on replacements due to efficiencies of newer vintage turbines and/or a lack of contracts to support those less efficient early vintage turbines and/or lack of contracts outright. Coincidentally, California's big utility companies have already bought most of the energy they need to meet the state's next target; one that requires 33% of electricity to come from renewable sources by 2020.

That's an odd bit of phrasing. Does that mean that they've bought the equipment with which to make that much renewable energy?  Or does that mean that they've bought the energy itself (ie, secured contracts to buy renewable power from BC or similar?)

 -k

The other day, none of them were working because there was no wind. The solar arrays would have been working fine but this was a desert in So Cal, not the great Great North Wet of BC.

Just south west of Vegas they have mirror arrays that focus light on a tower where water is heated to produce steam to run generators. They need to use natural gas to get them going in the morning and also incinerate any birds that fly close to the towers.

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

Yep I think we all understand that a solar panel array doesn't work when the sun goes down. But why ignore how much coal isn't burned during the day when the sun comes back up? And, how many birds do you reckon have died due to breathing in coal smoke and temp. change?

Except 1KW of incident radiation is only available for panels mounted on racks that follow the sun. Fixed solar panels don't get anywhere new that amount of energy for 10 hours a day. Maybe 2-3 hours tops. Moreover, any cloud cover reduces the available energy so unless you live in a desert a lot of days there will be less than 1KW even at peak times. Lastly, people don't stop using power when the sun goes down and they need electricity so it makes no difference if solar panels were 100% efficient and as cheap as paper, they would still be an expensive source of energy. The only thing that will change the poor economics of solar will be cheap batteries but we are a long way from that.

True that today's panels reduce efficiency by angle of direct sunlight, but that angle is improving (widening) constantly. The amount of solar radiation is based on what reaches the surface.

Yes we all know that cloud cover and nighttime hours are challenges that need to be addressed with storage. The South Australia battery project is going well, not only addressing those challenges but stabilizing the grid far better than traditional means.

Even if you never had any cloud cover, that is only a constant at the equator, everywhere else it varies with latitude and time of year.

Yes, but 1kw per square meter is a lot of energy. Total energy we receive from the Sun in an hour is about equal to the total energy we expend (in all forms) in a year.  Also remember that over 85% of our global electricity generation was originally sunlight. We just need to harness it efficiently. The 1kw value is the global average, yes polar regions receive less and equatorial regions receive more.

The amount of radiation reaching a surface is a function of the incident angle. That is why higher latitudes have less radiation. Fiddling with solar cells to perform better at high incident angles will only reduce the energy that can be used at low incident angles (i.e. they produces more consistent output for a longer time).
The SA arrays store a few minutes of power at great cost and exist to smooth out sudden swings in output. They compete with natural gas peaking generators but are a lot less flexible. What SA installations can't do is store power for use overnight or for a few days of cloudy weather. We are no where close to having the battery tech needed for the latter application which is why solar will remain a bit player in energy production for the foreseeable future.

Maybe you didn't know that Inuvik in the NWT receives only about 10% less hours of sunlight than does Toronto.And, in Inuvik you have 56 days in a row when the sun doesn't go down. Solar is becoming very popular in the NWT, especially as AGW increases.