My Position on Global Warming:
Reference information: http://www.geocraft.com/WVFossils/Carboniferous_climate.html
Warming – Likely. I have my doubts, and maybe it’s not to the extent they’re making out to be, but it looks quite likely. It appears it’s happened in the past.
Man Cause – Unlikely. I’ve seen plenty of evidence that it’s not the cause – especially when you go back millions of years and see there is no hard link between CO2 and temperature. But who cares, even if it is caused by CO2 how much of that is man made? If we eliminated all our CO2 now would it stop the permafrost in Russia from thawing and releasing yet more CO2?
Overall – Not a huge problem. If the Earth avg. temperature is normally much higher, then what are we afraid of? Life has existed through these times before, and if it has happened previously in a natural cycle, who we to stop it? Life has survived in the past. I think we just don’t like change, we don’t want to move our houses.
Solutions – Direct. If we want to solve the problem at all, we should take a direct approach and cool down the Earth.
I’m getting frustrated with the politics, media induced popularity and hype around global warming. Sure it could be happening – but to ram it down our throats and try to tell us, that it’s caused by CO2 is ridiculous. Especially given the scientific facts. But even if it was caused by CO2, according to the alarmists, changing our polluting habits will not make any difference for the next 100 years! So why spend billions of dollars which will have no effect? To me the answer is simple. If the Earth is warming up, if we attempt anything, cool it down directly.
Let’s look at the current popular equation.
Global Warming > Caused by CO2 > Reduce CO2 > Find technologies to reduce CO2.
My formula is:
Global Warming > Find technologies to cool it down.
If the problem really is that alarming, bypass the CO2, and get a world-wide protocol on such a direct solution.
Every day we are heated by the Sun. In the end it’s the Sun that’s warming the Earth – sure CO2 may be keeping more warmth in, but what we need to do is get rid of the heat. Take a look at this article: http://en.wikipedia.org/wiki/Solar_energy. The Earth is constantly being bombarded by 174 petawatts (PW) of thermal energy. This diagram (http://en.wikipedia.org/wiki/File:Breakdown_of_the_incoming_solar_energy.svg) shows how the energy is absorbed and emitted. 89 PW is absorbed by land and sea and that’s good, our plants bathe in the light – all living organisms (except a few) depend on the light and heat from the Sun, but it seems that at the moment it’s too much.
Idea 1 – Terrestrial Reflectors
The greenies are pleading with us to build solar thermal power plants in deserts – makes sense, but they’re enormously expensive. We can indeed benefit from this free energy, but I suggest we take an intermediary step which will cost less, cool the Earth and prepare us for future expansion of solar thermal power.
And we definitely don’t need that heat in the deserts. The solution…
Mirrors… glorious mirrors… actually solar thermal reflectors – there’s a difference… and lots of them. On average for every sq. m of Earth there is 1KwH of solar energy bombarding the earth – of course the average is higher near the equator and in deserts (where there’s less moisture in the air). Solar Mirrors can (http://en.wikipedia.org/wiki/Solar_mirror) reflect 93% of heat back into space. By reflecting enough heat back through the atmosphere and back into space, less is absorbed in the ground – where the heat is most absorbed into the lower atmosphere. Think about those hot days, when the bitumen is radiating heat, this is what makes it a hot day. If the Sun didn’t shine on the ground and the wind didn’t pick up the heat, you’d be fine. Now of course, we still need light and heat – let’s not go overboard…
The idea is to install and arrange fixed solar mirrors in the desert, but in a constellation best used for future Solar Thermal power generation. For power, one needs to track the sun to keep the light on a central solar tower, but we don’t need that to cool down the earth, just ensure the heat reflects up back into space. So the mirrors would be fixed – no tracking electronics or mechanics required, but they can still be mounted on stands which have the dual axis movement, they’re just locked until you upgrade them for power generation.
With a Solar Thermal Power plant (http://en.wikipedia.org/wiki/Cloncurry_solar_power_station) you want to generate electricity, there’s much more complexity and cost in this endevour. You need the tower, power transmission, tracking mechanics, and all the people to make that happen, then maintenence etc… A 10MW power plant costs about $31M and consists of about 54 towers, with mirrors covering 60,000 sq. metres (http://www.lloydenergy.com/presentations/Cloncurry%20Solar%20Thermal%20Storage%20Project.pdf)
How much would it cost to just have the mirrors? If the mirrors cost $25 / sq. metre (including installation), it represents $1.5M or 1/30th of the cost of the whole plant. (We’re not including land cost – which shouldn’t be a problem in the desert if it’s a Government backed initiative. Also remember, the mirrors don’t have the tracking mechanics which would cost a lot to install and calibrate). But if you spend a bit more you get electricity – you say? Well let me assure you that, even Nuclear (considered expensive) is cheaper to consume that Solar Thermal. And aren’t we trying to combat global warming?
Now in Equatorial and Australian Deserts the average is more like 2200Kw / M2 (http://www.off-grid.net/2004/07/10/how-much-solar-energy-is-there/). Those 60,000 mirrors would reflect around 132MW of solar energy back into space in an hour during the day (that must mean the solar thermal plant is only converting less than a 10th of the energy?). In a day (8hr peak) would reflect a whopping 1056MW of solar energy – that’s over 1GW! All for $1.5 million dollars.
So by pointing the panels into space, we can actually solve the problem. They want to spend billions to reduce carbon and tax many citizens at the same time. For $100 billion you could have 4 billion sq. meters of reflectors (For solar thermal the reflectors are spaced out – we’ll say one reflector in every 3Mx3M block – x9. This means it would cover ~60x60KM), sending back 88TW of energy per hour or 704TW back into space. That might be enough to tip the global warming scales in the other direction, pretty good considering they’re pouring in all that money which will have no effect (at least for 50-100years).
Also, imagine the environmental implications. The deserts could be cooled and in fact re vegetated… Or if the Earth cools enough, put in Solar Towers (over a longer time, as there’s no rush now) and reap the energy, pointing the mirrors back to the sky if Global Warming becomes a problem again.
Idea 2 – Space Reflectors [Best Option]
Only 89PW of the total 174PW of energy pounding Earth hits the ground. This means the terrestrial reflectors are about half as effective as if they were in space, and the energy still passes through the atmosphere twice, where it can be absorbed.
The idea is to put a sail in between the Earth and the Sun. Initially, I thought that you could just have a huge inflatable object floating in space. But then I remembered the solar winds (and Earth’s gravity – which is more of a problem because the object isn’t orbiting the Earth) – they would blow the object back to Earth. For this to work, you either need to place it closer to the Sun (where the Suns gravity over-powers the winds), or have many smaller stream lined objects – the latter seems more likely. For this to work, you would need to send a rocket up and then break out of Earths orbit, travelling to a place which maximizes the shading objects cover of Earth, while requiring no propulsion to maintain position. Then jettison the objects (likely near-vacuum “ballons”, which expand in space (vacuum)).
There would be no problem regarding having hard shaded spots on the Earth, as the Suns’ rays are not parellel. The objects would practically dim the sun very slightly.
To match Idea 1’s target of 704TW / day reduction = 24.4GW / sec. This would require a sail size of (8x 174*1000*1000ths of 127800490km2 =) 5.8km2 (compared to 4000km2 terrestrially). This size sounds achievable with one launch. If the sail was close to moons orbit (the sail would need to be slightly bigger – as the sun spot size increases as you approach the Sun – right near the sun is the size of the Sun’s cross sectional area), a 47,000KG payload can be delivered (http://en.wikipedia.org/wiki/Payload_(air_and_space_craft)) (perhaps you can go just inbetween the Earth and the Moon – the Moon would attract meteors etc.. preventing damage to the sail and if placed correctly, the moon’s periodical passing may pull the sail back away from the Earth, enough to counter the winds?). So a sail of 5.8km2 would need to weigh less than 47T. The sail would have to weigh 8g / m2 – (so you’d probably need a bigger rocket than the Saturn V). Not very comforting (@ 6.35 µm foil weighs 17.2g/m2). So let’s use multiple launches to have 100g / m2 material – therefore 13 launches @$150million ea. Therefore in total, with a cost of $1 / m2 for the material + launches, it would cost: $5.8Million (materials) + $1.95bn = ~ $2bn. (That’s compared to $100bn for terrestrial solution).
Now with the same $100bn you could have 50x the coverage = 1.2TW / sec (and because it’s in space you have 24hr effectiveness, so it’s 4 times as effective as the terrestrial idea = 29.3PW / day!). I would think very effective for the purposes of reversing Global Warming, in fact I think this is dangerous – you’re at risk of creating an Ice Age!
Costs (Comparison of Idea1 and Idea2 with 1PW reduction):
Terrestrial: To stop 1PW of energy hitting the Earth’s surface, it would cost about $573,032 trillion @ $25 / m2 for reflectors. (I’m not saying you need to stop 1PW – but this is good for comparison).
Terrestrial Workings: Surface Area of Earth = 510000000km2. Sun affect = 1/2 of Earth = 255000000000000m2. 1 / 89th of 1/2 earth’s surface = 5,730,337km2. @$25 / m2 = $143258Trillion. Must x4 because the mirrors are only effective 1/4 of the day(all in one spot) or 1/4 as effective all the time (spread over the earth – near equator). So, $573,032 Trillion.
Space Sail: To stop 1PW of energy hitting the Earth (remember you would need 1/4 less material because it’s always in effect – unlike the terrestrial solution (8hrs / day)), it would cost about $800bn. So if the sail was thin enough and you could launch it in one rocket, stopping 1PW of energy is feasible – and overkill i’m sure. But certainly looks like the best option, with extra thought needed into the sail material (thinner is better – lighter – cheaper)
Space Sail Workings: Diameter of Earth = 12 756.2km . Sun spot on Earth = 127800490 km2. To reduce 174PW by 1PW, you would need to block 1/174 of the Sun Spot = 734,485km2 of blocking (compare that to 5,730,337km2 of reflectors required on Earth (7.8x), plus in Space they don’t necessarily need to reflect – space is cold – they can absorb and cool, and the sail can potentially be one big thin sail (with holes to prevent it moving)). Because you’re building one huge sail, and only “install” once, you can get a much lower per-m2 price + install costs. (We will put aside the fact that for this scale you would need thousands of launches – that doesn’t scale well – so let’s pretend it only needs one massive launch ~ $65bn special purpose delivery). At $1 / m2 it would cost $734,485,000,000 or $735bn + $65bn (with one super launch). If 5.8km2 requires 13 Saturn V launches, then this requires 126,635 launches = ~ $19,000 trillion.