Obama has made no bones about his intention to transform America’s energy infrastructure into a big, green machine. And with an overwhelmingly Democrat House and a supermajority in the Senate, the country’s energy generation and delivery systems are likely to get greener and greener in the months and years ahead.

We’ve already seen a big push toward the creation of so-called “green jobs” in the latest vote by the House over cap-and-trade legislation, but the real sod on the green front can be found in the American Recovery and Reinvestment Act, i.e., the stimulus bill.

In February, the president signed the American Recovery and Reinvestment Act into law. The bill included more than $70 billion in direct spending and tax credits for clean energy and transportation programs. In addition to the green spending spree, other legislation has been passed recently that’s designed to help spur growth in the alternative energy sector.

Given the new green milieu in the country, the question for investors now becomes: How can we make money? Or to put it the way ChangeWave Investing founder Toby Smith once asked me, “How can we make green by being green?” That question led us to write an entire book on the subject, aptly titled Billion Dollar Green: Profit from the Eco Revolution.

To be sure, conditions in the stock market, the alternative energy space and Washington, have changed a lot since the book’s publication last year, but what hasn’t changed is the need for investors to find the best-of-breed alternative energy stocks.

And with that in mind, let’s take a look at five alternative energy stocks that just might make your portfolio a whole lot greener.

Alternative Energy Stock #1 – Suntech Power Holdings (STP)

China-based Suntech Power Holdings (STP) is one of the largest solar energy companies in the world based on production output and capacity of solar cells and modules.

STP has developed an advanced process to manufacture photovoltaic (PV) cells cost-effectively at a large production scale with high conversion efficiencies (i.e., how much sun energy is converted to electrical power).

This technology will likely help STP outshine the competition in the solar space, and that means investors are likely to see their portfolios lit up by the power of STP shares.

Alternative Energy Stock #2 – Cree (CREE)

Sometimes referred to as solid-state lighting, LED lighting technology creates light with less heat than incandescent or fluorescent bulbs. Solid-state lighting uses a semiconducting material to convert electricity directly into light, and LED bulbs are generally three to four times more energy efficient than incandescent bulbs.

The best company in this space is Cree (CREE), which developers and manufactures the semiconductor materials used for LED lightning. Cree’s LEDs have the ability to increase energy efficiency and performance.

Oh, and if you’ve been in the stock lately, the shares have also increased your portfolio’s performance.

Alternative Energy Stock #3 – PowerShares Water ETF (PHO)

We’re about to see a renewed emphasis on the rebuilding of our nation’s water infrastructure. Now, there are plenty of companies serving various niche water infrastructure markets, but rather than trying to pick one, why not use a bucket?

The bucket in this case is exchange-traded fund PowerShares Water Resources (PHO), which gives you exposure to the best companies in the water industry. The fund has a solid balance of holdings, with no single stock representing more than 5% of the total portfolio.

If you want to make some green in your portfolio, then taking the aqua route is a good way to do so.

Alternative Energy Stock #4 – Itron (ITRI)

Smart grids require smart meters, and there is no better smart meter maker than Itron (ITRI). As the leading provider of smart meters for electricity, gas and water utilities, Itron is uniquely positioned as the go-to smart meter maker across the energy measurement spectrum.

Itron has a more than 50% market share in the electric smart meter segment in the United States and Canada, and the company could dominate the smart meter space.

With more than 3,000 customers worldwide, and tens of millions of smart meters operating throughout the globe, Itron is definitely a stock to watch.

Alternative Energy Stock #5 – Echelon (ELON)

Echelon Corp. (ELON) is one company riding what’s known as the green building wave. The company designs, builds and sells networks that connect machines and other electronic devices for the purpose of sensing, monitoring and controlling the world around us.

You see, before you can save energy, you’ve got to know where and when that energy is used (or wasted), and that means you need some very smart devices that can provide you with the data necessary to do so.

The future of greener buildings is in what’s called energy consumption or “negawatt” management. The idea behind negawatt management is that a kilowatt saved is a kilowatt earned. The easiest, fastest, cheapest and, ultimately, cleanest form of energy is the one that never has to be produced in the first place. But before you can save a negawatt, you first have to identify it.