At ChangeWave Investing, we want to be invested in the multi-billion-dollar solutions to the billion-dollar problems in the alternative energy space – and the companies that will make billions because of them.

Here are the big problems with several alternative energy solutions:

1) Cellulosic ethanol: The enzyme required to produce it is way too expensive and the pre-treatment process wastes too much sugar.

2) Geothermal energy: It's hard to access magma without inadvertently causing a little seismic activity.

3) Liquefied coal: Turning coal into liquid fuel requires vast amounts of water – another dwindling resource, particularly in coal-producing regions. But just imagine how much money the company will make that's able to turn coal into energy that we can use in our cars.

4) Nuclear energy: This is the political third rail – no one wants it, and there is no 110% safe place to put the spent fuel.

5) Solar power: We've made a ton of money in solar energy at ChangeWave Investing, but highly-refined silicon panels may never be as inexpensive as fossil fuel.

6) Wave power: There are only 40 sites on Earth that offer tidal ranges greater than 16 feet, and those only work about 10 hours a day. So, we need a technology that could duplicate that in order to make money from this resource.

7) Wind power: We also have a recommendation in wind power, but it's an intermittent power supply, i.e., when the wind doesn't blow, there's no energy. So far, no one has come up with a way to store and transmit that energy.

8) Fuel cells: It currently requires more energy to create power than the power generated by the fuel cell, which makes them very inefficient.

The greatest wealth creation in the next 20 years is going to come from being invested in the companies that find the solutions to these multi-billion-dollar problems. We're invested in a number of companies working on them, and you can be, too. Plus, there are dozens more that are coming public in the next two-to-five years.

You simply have to be in this space.

Let it Bloom

I'll give you a great example of a breakthrough company in fuel cells: Bloom Energy.

With the backing of Kleiner Perkins Caufield & Byers (KPCB), other big investors like Wal-Mart (WMT) and Morgan Stanley (MS), and a few small players, like me, its vision is to use solid-oxide fuel cells to allow homes or stores to generate all of their own electricity.

The fuel cells would use, but not burn, hydrocarbon fuel, and produce half of the carbon dioxide that today's power plants do. One fuel cell should be enough to serve one home, and homes could sell the excess power back to the energy grid.

Bloom's biggest hurdle is cost. It needs to get the price of its machines below $10,000 apiece, perhaps with some added tax incentives from the government.

Next year, this company will sell $250 million worth of its power cells to Wal-Mart, because Wal-Mart wants to be the greenest company in the world. And what Wal-Mart wants, Wal-Mart gets.

Lighting the Way to Profits

Another great example is a company currently on the ChangeWave Investing Buy List that produces the innards of solid state lightbulbs, which are going to replace the incandescent lightbulb. On average, these new bulbs last 37 years and cut your power consumption from lighting by 90%. (Click here to get in on that stock today.)

White light-emitting diodes or LEDs are the new lightbulb. We're seeing mandates to switch from incandescent bulbs to more-efficient lighting in many countries (besides the United States) like Australia, Europe and Canada – and I bet you're going to see it in China, too.

Building Generational Wealth

But, let's go back to my original point. Where we are in the green energy trend is similar to when Ford, Firestone and Edison were just getting started with their life-altering inventions.

We have the potential for huge growth in this space – I'm talking about going from $10 billion to $200 billion a year in sales and services – because it's the way of future and because being held hostage to rising oil prices not only kills our economy, it's a threat to our security.

This month NBC had a special "Green Week," and usually when NBC starts talking about something, I say that marks the end. But this time, they got it right – the Green Energy Wave is here.

This wave is only just beginning, and for you, as an investor, it's the chance to build what I call generational wealth – wealth that will last not only through your years, not only through your children's years, but through your grandchildren's years.

Whatever you want to call it – alternative energy, green energy, green tech, clean tech, sustainable energy – this space will be the greatest wealth generator of the 21st century. You simply can't afford to miss this. Ride the Green Energy Wave with ChangeWave Investing. Click here to get your 90-day, risk-free trial.