
An ambitious solar energy project on a massive scale is about to get underway in the Arizona desert. EnviroMission is undergoing land acquisition and site-specific engineering to build its first full-scale solar tower – and when we say full-scale, we mean it! The mammoth 800-plus meter (2625 ft) tall tower will instantly become one of the world’s tallest buildings. Its 200-megawatt power generation capacity will reliably feed the grid with enough power for 150,000 US homes, and once it’s built, it can be expected to more or less sit there producing clean, renewable power with virtually no maintenance until it’s more than 80 years old…
Enviromission’s solar tower is a simple idea taken to gigantic proportions. The sun beats down on a large covered greenhouse area at the bottom, warming the air underneath it. Hot air wants to rise, so there’s a central point for it to rush towards and escape; the tower in the middle. And there’s a bunch of turbines at the base of the tower that generate electricity from that natural updraft…
Then, raise that tower up so that it’s hundreds of meters in the air – because for every hundred metres you go up from the surface, the ambient temperature drops by about 1 degree. The greater the temperature differential, the harder the tower sucks up that hot air at the bottom – and the more energy you can generate through the turbines.
The advantages of this kind of power source are clear:
Because it works on temperature differential, not absolute temperature, it works in any weather;
Because the heat of the day warms the ground up so much, it continues working at night;
Because you want large tracts of hot, dry land for best results, you can build it on more or less useless land in the desert;
It requires virtually no maintenance – apart from a bit of turbine servicing now and then, the tower “just works” once it’s going, and lasts as long as its structure stays standing;
The critter is scheduled to start producing power in 2015. If we had a public power company that made it to the 20th Century – if not the 21st – we could do something similar here in New Mexico.
From a separate temporal view, we’ve known how to evaluate the physics of propositions like this for decades. Computer modeling of the process, processes like this, isn’t new either. But, to return to my theme song about computational analysis, the amount of computing horsepower easily and cheaply available to recheck the physics, the details of design, has scaled up beyond comprehension compared to even a decade ago. And software to match sits inside off-the-shelf laptops with graphics sufficient to educate any VC worth his or her greenbacks on how well a project like this one will produce a return.
The only people who aren’t likely to get it – are the fracking politicians and bureaucrats who sit in the way of any kind of progress in this nation. And that could have changed by now, too – but, hasn’t.