The movement founded by people pejoratively labeled as tree-huggers, enviro-Nazis and hippies has now been joined by governments, multinational corporations and the armed services.

Nineteenth-century philosopher Arthur Schopenhauer famously said, "All truth passes through three stages: First, it is ridiculed. Second, it is violently opposed. Third, it is accepted as self-evident."

From my perspective, so-called Cleantech is rounding the second stage and headed into the third. Here’s a rundown of recent news stories that demonstrate how Cleantech is moving forward, both as a concept and burgeoning industry.

A Solar Sahara

I was at a publishers' conference this past weekend and, while the event can become a bit tedious, it's always a pleasure to see my colleagues from around the world. I'm especially tight with a group from a German publishing company.

In our conversations about products and technology, one of them noted proudly that German companies will be covering the Sahara in solar panels. The project is called Desertec, and the goal is to organize a consortium of 20 major German companies--including E.ON, RWE and Siemens (NYSE: SI)--that will put up around EUR400 million in money, time and materials.

The group will work with German Aerospace Center (DLR) and build a number of solar thermal farms throughout North Africa in the hopes of producing 100 gigawatts (the equivalent of 100 coal-fired power stations) of capacity by 2050. The power would be transmitted back to Europe via high-voltage DC power cables.

The coolest thing about this project is its sheer magnitude--and the corporate and governmental enthusiasm for taking it on. Also, it's interesting to note that DLR is working on next generation high-speed rail that cuts energy usage dramatically and increases train speeds substantially. And high-voltage DC power cables have only been a concept; a project like this could make the technology commonplace and be a real game-changer for Smart Grid applications.

One unique concern that’s cropped up about this proposed project is the Albedo Effect. The albedo is essentially the planet's reflectivity of the sun's rays. Leaves have a lower albedo than the desert, and water has a greater albedo than houses. Broadly speaking, the Earth's albedo is 0.39; it reflects 39 percent of the sun's rays back into the atmosphere.

Many scientists suggest that it would be prudent to paint roofs white to enhance the reflectivity and reduce global warming--a simple idea that would have a significant impact if implemented globally. On the other hand, many smart people are getting concerned with an over proliferation of photovoltaics (PV). Because PVs absorb light and store heat, the new concern is that we may not increase the albedo by adding too many PVs to the planet.

If that were the case, it would be better to stop using solar and simply burn fossil fuels.

Eat Your Dog

New Zealand authors and sustainable living architects Robert and Brenda Vale have published a new book, Time to Eat the Dog: The Real Guide to Sustainable Living, which compares the ecological footprints of a menagerie of popular pets with those of various other lifestyle choices. From their conclusions, our domesticated friends don't compare favorably to other modern lifestyle choices--for example, rolling around town in your mammoth SUV.

Yes, that's correct. Your Toyota Land Cruiser has less of a carbon footprint than your lovable pooch.

Wet Energy

Despite being the most mature renewable energy source, hydropower is probably the alternative that’s least talked about. The newest iteration of the old concept of funneling water through a turbine is wave or tidal energy.

In these technologies the goal is to derive energy in a passive way from a continually active source--in this case, water flows in oceans and rivers. There are a number of projects already underway in Canada, the UK, Spain and the US.

In some areas, windmills and solar panels just aren’t practical. But the open ocean has a lot of promise.

With the help of design and engineering firm Ansys, a fledgling breed of energy generators is taking shape. Scotland-based Green Ocean Energy has developed two generators that use two "arms" to ride the waves, using the flapping motion to run a generator. Ocean Treader and Wave Treader are the company's new ideas.

A number of Ocean Treaders are placed over a stretch of ocean, and the collected energy is then shipped back to shore. For the Wave Teader, the generator is a complimentary power source, as the treader serves as a floating base for a wind turbine.

This is a very interesting space because effective technology is much more accessible than it is for solar, which is transitioning from a low-efficiency baseline (lower or equal to internal combustion engines) to something slightly higher. Also, because hydrodynamics vary according to what body of water you're attempting to derive energy from, there are myriad ways to design equipment. Keep an eye here.

It's a Bird.  It's a Plane. It's a Solar Collector in Space.

Well, it looks like the space race is on again. This time it’s the US versus Japan. And it's not about racing to the moon but harnessing solar power in space and shipping it to earth. Space-based solar power is a science-fiction concept that’s moved from the mind of Philip K. Dick to the research and development labs of Mitsubishi and Pacific Gas & Electric (PG&E).

California-based PG&E has been working with a closely held (and tight-lipped) company named Solaren, which has no website to speak of and is apparently made up of former defense tech and info tech folks. This project has been publicized for almost a year now, but there hasn't been much headway, other than lip service by PG&E that it's committed to the project and will begin development soon.

Japan's timeframe on their project is about three decades, so my money is on the US consortium to get something up and generating first. The initial Japanese project is a 4 square kilometer solar collector that will generate 1 Gigawatt of electricity that will be shipped down to Earth via radio frequencies, reconverted to electricity and shipped to the consumers.

Bottom line: There's a lot of private money going into Cleantech, and government money is shoring up these investments. That adds up to an industry that will benefit many of the old industries out there.