My time recently has been taken up in expanding the panocracy.net website so this time we're examining a less weighty matter: population.
August in Scotland means it's wet and our population is dropping as the rain from the grey clouds, continuously and inexorably. These two facts may be causally connected.
Or not.
A recent substack article prompted the somewhat light-hearted calculation below (please check my arithmetic which is usually lamentably unreliable!)
See Robert Malone’s article for a summary of US plans to restrict the world's population to 8bn or so.
The Kissinger Report of 1974 suggested that we'd all end up as Soylent Green if we didn't repent of our sins of fornication before the world's population reached 8bn or thereabouts.
I'd be surprised if no one else had thought any further along the lines of Kissinger’s document in the fifty-odd years since its publication. And even more surprised if any sins had been repented of.
In the positive, pro-humanist spirit of panocracy I wanted to concentrate on how we might give all the 8bn good folks currently on our little blue dot the means to live the good life.
With a net-zero energy system of course.
A long time ago in pre-internet days I wondered how much energy it would take to give the entire population of the world the same lifestyle as the average American, the American standard of living being the gold standard. Back in 1974 that question was hard to answer but the internet makes it easy now.
Of course, not everyone wants that lifestyle but I'm guessing that all these folks are not immigrating to the US because they're desperate for root beer.
This is really a question about energy usage – US citizens seem to require a lot of it. We can do an order-of-magnitude calculation to tell us how this scales up to our current world population of around 8 billion souls (Bill Gates is therefore excluded).
So how much energy does the average American consume? Sources differ a little in overall US energy usage but it makes no real difference for our order of magnitude calculations.
We take a value from statista's 2021 figures for the USA : 92.97 ExaJoules is around 93*1018 Joules. A number that big doesn't mean much to me and possibly not a lot to you either!
As a check, I looked up the equivalent EIA figure which is 97.3 quadrillion BTU or 102.7 * 1018 EJ, which agrees to within 10% - so we're in the right ballpark here.
The US population was 332,031,554 on 1st July 2021. Such precision (!) - and probably out by a million or two anyway but it will do.
This gives us 2.82*1011 J per American per year.
To put this in perspective, an adult human needs about 2000 calories per day or just over 3*109 J per year. Now, a dietary ‘calorie’ is really a thousand physical calories (h/t to SaHiB) so the average US citizen uses about 100 times as much energy as they need.
This is spread across industry, commerce and government as well as home heating, cooling and travel, plus John Kerry's wife's private jet.
All that energy is supplied mainly by fossil fuels:
35.4% Gas, 23.2% Oil, 11.6% Coal, 8.1% Nuclear and the rest (21.7%) by renewables
What would we have to do to make it so that the entire world population lived as well as the average American?
We'd have to supply 2.82*1011 * 8*109 J/yr which equates to 2.256*1021 J per year.
That seems like a shedload of energy so to put it in perspective, let's compare it with the energy the earth receives from the sun.
The Earth intercepts around 180*106 GW of the sun's energy or 1.8*108 * 109 * 31.5*106 J/yr which reduces to 5.7*1024 J/yr
So the earth receives about 2000 times more energy from the sun than we would need to enjoy our high energy humanity. There’s plenty of solar energy to go round.
Now for fun let's see if we could supply all the energy we need with solar photovoltaics – solar panels.
Solar Energy
A lot of factors conspire to reduce that 2000:1 solar energy surplus:
bandwidth - That figure includes all radiation bands from radio to gamma rays but only a narrow band of visible energy is any use for generating electricity.
solar cell efficiency - Today's solar panels produce about 150W per square meter under ideal conditions – 25oC in full sun (https://www.waystosaveenergy.net/2021/04/solar-energy-per-square-meter.html)
latitude – solar panels don't get much light at high latitudes and they're very inefficient when they get hot. So the tropics aren't much good either.
weather – clouds are bad news too
shading – panels lose a lot of efficiency under conditions of partial shade like trees or nearby structures
night – obviously solar panels produce nothing after dark. This doesn't affect what we have to say below because our figures are averaged over day and night.
All these factors make accurate calculations very difficult and unreliable as many assumptions have to be built in.
So to calculate how many panels we need we won't use our above figure for annual solar irradiation but instead we'll use our own solar panel array which was installed in 2011. This is a guide to how much power we can practically expect and therefore how many panels we would need for a given power output over time.
In the case of our own solar panels the actual power generated has been only 84% of what was predicted at installation time by the installers using an array of parameters like latitude, roof angle, etc. which just goes to show how hard it is to get a good estimate. And how shit the Scottish weather is.
Our Solar PV Array
It's at Latitude 55N and has PV cell area 16.5m2. It's rated at 2.5kW which means that's what it produces under ideal conditions (and it has done so, albeit for brief intervals).
From 22-sep-2011 to 31-jul-2023 (4330 days) it produced 21390kWh or 4.94kWh/day or 1803kWh/yr (the installer predicted 2146kWh/yr).
Which works out to be 109.3 kWh/yr/m2 or 3.9*108J/yr/m2
So to provide 2.256*1021 J/yr would require 2.256*1021 / 3.9*108 or 5.8*1012 m2 of solar panels which equates to 5.8*106 km2 – nearly six million square kilometres or two and a quarter million square miles.
This is about three quarters of the land area of Australia.
Australia is a pretty empty place but we might expect some pushback from its inhabitants.
Making Solar Panels
Setting aside any possible objections from our bronzed, well-muscled antipodean cousins, would the construction of all those solar panels be a significant energy overhead?
It takes about 200kWh of energy to make a single 100-watt (rated) solar panel. This would be 0.66m2 in area.
To manufacture our world energy array will need 200kWh * 5.8*106 km2 / 0.66 m2 which reduces to 1.76*1015 kWh
That's a lot but we have to amortize it over the expected lifespan of a solar panel of 25 years to give about 7*1013 kWh per year replacement energy requirements.
This is less than a millionth of the energy the array would supply so the good news is it wouldn't kill us to do it.
Goodbye, Belgium, Germany, …
We've assumed that the rather pitiful energy our solar panels provide here in Scotland would be easily achievable at most other latitudes. If we could get two or three times the efficiency then we'd only have to occupy half or a third of Australia.
Then again, we'd need to site panels all over the world to supply power to the night side and we'd have to have a pretty nifty power distribution system to distribute it all.
And we haven't taken account of energy losses in transmission or storage or maintenance. Our repairmen would have to get to the panel they need to fix and there would be a trillion of them in the way.
If we wanted storage to tide us over the odd occasions when the sun doesn't shine in Oz then it's possible to work out what kind of land area we'd need to house the rather large number of AAA batteries we'd need. But you probably have the gist of the thing by now.
We've ignored other sources of renewable energy like wind or geothermal so a mix of these technologies might allow some of the Aussies to hang on to their homes on Bondi beach. They would be very big homes as Australians would become very, very wealthy.
We hope our Australian friends will look favourably on this venture.
You're off 3 orders of magnitude. You forget, dieticians call a kcal a "calorie". You're not a shrew, mate!
You forgot about fusion. I know it’s always decades away but I saw a very interesting YouTube clip the other day of a non-Tokamak fusion reactor (about 7 or 8 metres long and 2 metres or so in diameter) which avoids all the engineering problems of the Tokamak design. So one never knows what may be around the corner.