Capacity Factor: Why solar and wind are impossible fantasy.

Brian Hanley
11 min readSep 10, 2021
The red line below is a real demand curve. The blue line is a real solar supply curve. . Figures, Germany.

I am not the only one to criticize the solar and wind fantasy. So did Clack, et al. Unfortunately, in scientific papers plain language is rarely found, so laymen are left with the fantasies of propagandists for big oil, gas and coal. Make no mistake about this — those anti-nuclear and pro-solar activists are promoted by big oil. David Brower was funded by big oil — $200,000 in 1970, which is the equivalent of $1.3 million today — to take over the Sierra Club and make it anti-nuclear. Mark Z Jacobson at Stanford has received 100% of his grant money from oil company cutouts. The same is true of Energiewende, which was started by former Chancellor Gerhard Schroeder, who is the chairman of the board or Rosneft, in charge of selling oil and gas to Germany. You see, they know solar and wind cannot work. But let’s get to the technical problems with solar and wind, starting here with solar.

Keep in mind that the grid must exactly balance demand to supply 24 hours a day, without fail. If there is not enough supply, it must switch off sections of the grid. If there is too much, it must reject, dump, or store the excess.

“Not sure I understand the argument about renewable intermittency causing us to burn more fossil fuels. We’re technically burning less if we only have to burn in the off hours.”

https://pveducation.com/solar-concepts/solar-system-output/ The area under the curve also is your fraction of full capacity you can get from the solar panel.

Problem is that if you look at that graph above, there are huge deviations during the day — not just between day and night, between what the solar panels are providing, and what the grid needs. The red line is demand, and the blue is solar supply. To the left is a graph of what real supply looks like.

Another thing renewable detractors always fail to take into account is the massive leaps on energy storage we’re seeing every year. The 2022 Ford F150 Lightning will be able to power your house if the grid goes down.

Brand new, the F-150 Lightning fully charged is 115–150 kWH. Household use averages 29 kWH per day. But during heat events, for instance the 2021 summer heat wave, use can double or more, and those EVs are not supposed to be grid connected. You would need a special circuit installed in your home to switch off the grid and use your truck’s battery. The driving range of a new truck, full-charge, is 230–300 miles, without load. That drops with loads, but let’s assume normal driving of 100 miles per day, which is 43.4–33% of capacity. When you arrive home is when you will need that power, and it will happen on the worst possible day when temperatures are in the 115 to 120 F.

For maximum battery life, an EV battery should not be discharged below 20%, and should not be charged above 80% of capacity.

Energy storage is more complicated than it looks, and the requirements are beyond huge. 96 gigawatt hours would be roughly half the needs of a medium large (6 million people or so) city for 1 or 2 days, and that is 240 times the size of the largest installation yet, which is 400 megawatt hours and will take 5 years to complete building. Let’s figure 75% of global population (6 billion people) will have electricity in the future, population will not grow, per capita use will not grow, and in emergencies, only half of that population will get electricity for half a day or so. Batteries (which would need replacing every 10 years) would need to store 96 trillion watt hours. This translates to 6 billion EV batteries or more, when we are wondering how to meet the requirements for just 30 million EVs. This is very expensive electricity already.

So, let’s get into capacity factor which is the amount of energy you can expect from your solar panels. We will use a simple, one house “off the grid” example in order to see how this really works, because “off the grid” just means you run your own little grid locally, just for yourself. I will develop this step by step for novices.

Typical home solar panels are rated at around 7.5 kW. People say, “Great, you get over seven thousand watts of power from them!” Well, not really…

Let’s take a 100 watt panel. Let’s slow and synchronize the Earth’s rotation so the the Sun is always overhead at the perfect angle for my panel.

Let’s look at the power produced over the course of 100 hours. It would be 100 watts X 100 hours, that’s 10,000 watt-hours, or as it is more commonly expressed, 10 kWH, or 10 kilowatt hours.

But we can’t park the sun overhead. That 100 hours is a little over 4 days, so let’s pretend the sun rose and set instantly each day and each day was 12 hours of day and 12 hours of night… and let’s DEFINITELY ignore the impossibility of making that happen. Well, now my 100 watt solar panel actually makes 50 kWH.

If we make a fraction of the actual power divided by the power rating on the label of the device, we would have capacity factor and it would be .5 or 50%. Great, you say. Still sounds good.

We’re not done.

The sunlight peaks in the middle of the day and falls off dramatically in morning and late afternoon. Clouds. Rain. Smoke including smoke mud left on panels courtesy of morning dew. Dust, including dust on the panels. Snow.

Days aren’t divided 50/50 between day and night. Length of day and night varies by latitude and season and weather.

All of those are factors that make solar capacity factor just a little over .3 in the very best case (much of the globe is considerably less)… on average… taken over a long time.

But, if you haven’t noticed, there is still a problem. Your electric heat pump doesn’t care about averages. If it needs power at 3 AM and your solar panels are sitting in darkness, then power has to come from something else.

Batteries? Critical factors are energy storage capacity, discharge power capacity, and battery life at the rated charge/discharge capacities.

An example: you have an early plane to catch… It is SUPER hot outside… you wake up at 3 AM. You need to take a shower, turn up the AC a bit, make breakfast, watch the news… oh, and throw some clothes in the dryer from last night’s wash.

Your house is all electric according to the new environmental rules.

Heat pump 15 kW; Water heater 4 kW; Toaster 1 kW; AV equipment .3 kW; Dryer 2 kW. Other things are running, too. Lights, refrigeration, device chargers, hair dryers 1.2 kW. Ignoring those other bits, like lights, we are looking at a burst of:

Around 22 kW on this morning dash when you just need things to work for you on your way out the door.

Let’s throw that load onto your Tesla Powerwall, so we can do all this while saving the planet. The second generation power wall can deliver 5 kW (7, if you push if for less than a minute… so we will use 4 powerwalls for this exercise. (But really it should be 5, because pushing your batteries to deliver peak power will age them faster, which is very expensive in the long run.)

Installed cost of one Powerwall is about $13,000.

Five Powerwalls ganged together to feed this scenario: $13,000 x 4 = $52,000.

You have to be in the class that owns a Tesla car to consider this affordable. Don’t forget replacing them every 10–12 years, if you treat them nicely, and never drain them all the way — which happens pretty frequently with EVs, and should happen easily with Powerwalls as well.

Maybe 1% to 2% of the USA’s population can afford this. (Remember that when you think about expanding this to cover the world with electrical power — who is going to pay for that capacity —unlikely that you who are reading this can afford your fair share.) Replacing every 10–12 years or so, over 20–25 years, you will pay $52,000 x 3 = $156,000 for batteries, and that doesn’t include installation costs. (First you must buy the initial system, and then replace batteries twice.)

But we are not done — We didn’t factor in the solar panel oversupply requirement if you use batteries, and the seasonal cycle. The solar panels must be able to store enough power in a time period, timeX, to be able to replenish them to carry the home through some time period timeY. For this exercise when we were just looking at your house, that creates a little mini-grid that illustrates the problem.

The usual proposed numbers are that the batteries should be able to hold the home for 3 days (timeX). And the batteries should fully charge in 2 days (timeY). But batteries are supposed to kick in mostly at night. For simplification, we will assume night use only for batteries. That means that the house must run off the solar panels during the day, and they must also have enough left over to charge the batteries for 3 days in 2 days. Do the math on that, and you need 1.5 days + 1 day of daily power production capacity in the solar panels, or 2.5 times what the house will actually use in one day!

However, this worst-case need scenario doesn’t kick in except for a few times, generally in winter months. The rest of the time the panels will be dealing with full batteries. So that means that most of the year, the solar panels will throw away 60% of their power generating capacity (or a lot more — we are getting to that). It takes 2 years for modern panels to pay for themselves in electricity. Dumping 60% of power means 40% is used, so it now takes 5 years for panels to pay back the energy used to make them. “Ok,” you say. But we are not done.

You may be thinking,But the grid makes this work by taking up all or most of that power in the real world.” Yes, sometimes that is true as long as total grid power is not overbuilt (it is in Germany for summer peak), but this is only when you are connected to the grid. (And remember that our one house scenario is a small model of the whole grid.) And if you don’t overbuild, then you must supplement with — fossil fuel, nuclear or hydro.

Hydro is the one everyone talks about — pump water uphill and solve everything. It is central to Mark Z Jacobson’s renewable fantasy that plentiful water will always be available. Looked at lake Oroville lately? The assumption that plenty of water is available for pumping to use for energy storage is nonsense. (We are doing this for one house, off the grid so that you can see what the problem is for a big grid. It’s the same problem — just much bigger.)

Lake Oroville, July 22, 2021 https://www.mercurynews.com/2021/08/05/lake-oroville-reaches-all-time-low-level-hydroelectric-plant-will-shut-down-for-first-time-ever/

I have had people tell me things like: We can just pump seawater into the Sierras! But I worked in civil engineering, and even the standard method of lining with bentonite is fiscally unfeasible for any significant size valley. And if it could be done it would not keep brine from penetrating into the underlying soil and rock, which would flow down hill and come out as springs and penetration of groundwater aquifers in the Central Valley. This would poison anything it reached. The brine that penetrated would not be salt water like the ocean. It would be concentrated brine, because such a reservoir would have to be open to the air. Replenishing endlessly with more salt water would slowly produce more and more concentrated brine. That brine would run back downhill to generate power and be much warmer than normal temperature. Let’s remember that the supposed reasoning for shutting down Diablo Canyon nuclear power plant is the effect of slight warming the Pacific near the plant. (No meaningful effect on sea life is documented, so the discharge would be ok.)

But there is a problem, sun energy varies during the year. We did this calculation presuming that the solar generating capacity was the same all year round. This might work reasonably well near the equator, and it’s bad enough. Most of the industrialized world is not like this. And none of the future inhabitable world of global warming is like this. That future inhabitable world has been predicted to be above the 40th parallel due to climate change extreme temperatures. (Or so we thought, until the recent heat domes in the north that hit 120 F for several days. We are probably in much more serious trouble than we thought.)

Black line is the red demand curve shifted down (because shifting the blue line up is not practical here) until solar can fill the batteries for winter. All the energy above the black line would be thrown away — excess capacity that would not get used. Here, that is over 90% of all the PV energy possible to generate. Wind has a similar, but different problem with overcapacity needs.

So, now let’s add in the seasonal cycle.

What we have to do here is to add solar capacity until the blue line can intersect the red line to the point that we can charge our batteries at the bottom of that cycle. In the image to the left, that is shown in black. If we were to do that, we would not be throwing away 60% of the power. We would be throwing away all the power between the red line and the blue line. Shift that red line way down to the bottom. Essentially, what this does is force us to throw away around 92%-97% or so of all the potential solar generating power for our system. Now it takes 25–66 years to pay back the energy used to make them from our panels. Modern panels have a projected life of 25 years. We have not included energy required to make the batteries.

We will never receive from the system the amount of energy required to make it, let alone install it. This is a net electricity consumer. That means it is impossible.

In this exercise, your single home has its own “grid” that it uses to distribute power to the house. Scale it up to a state or national level and you haven’t changed anything but the size and cost. The problem remains mostly the same.

Well, in fact, you have changed something when you scale it up. You will run into the limits of minerals we have to make things like batteries. You will also run into limits of rare earths for solar panels.

https://www.abirthdayplace.com/products/abpid09067-white-unicorn-rainbow-hair-space-background-ringed-planet-edible-cake-topper-image

What this really means is that the idea of a solar powered world is an impossible fantasy, literally less feasible than providing a real live unicorn to every child that wants one, complete with rainbow colors of mane and tail. Not joking.

The solar power fantasy needs to be buried where it belongs. It can practically supplement a grid with 10%-15% of total power. But it isn’t necessary, it is costly, and causes difficulties operating the grid.

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Brian Hanley

Peer publications in biosciences, economics, terrorism, & policy. PhD - honors from UC Davis, BSCS, entrepreneur. Works on gene therapies & new monetary models.