A year ago, former Fool Toby Shute and energy executive John Moore co-wrote a superb book titled The Hidden Cleantech Revolution: Five Priorities for Securing America's Energy Future -- Without Breaking the Bank.

In their eminently readable and comprehensive (albeit not unnecessarily lengthy) work, the authors dealt with the current and likely future of our all-important energy world. They limited their focus to fossil fuels, which, they pointed out, account for 84% of our primary energy supply. In looking toward a short-term shift to clean fuel sources, they said, " … wind, solar, and hydrogen can't possibly displace oil as our No. 1 source of transportation energy in the next decade or two." (I might have moved the bar to two or three decades.)

The travelin' man
President Obama had this to say in his energy policy speech at Georgetown University in late March:

I've visited gleaming new solar arrays among the largest in the world, tested an electric vehicle fresh off the assembly line, and toured once-shuttered factories where they're building advanced wind blades as long as a 747 and the towers to support them. I've seen the scientists searching for that next big energy breakthrough. And none of this would have happened without government support.

The final sentence obviously presages continued subsidies for "renewable" or "green" fuels. On the solar side, that likely includes benefits for companies such as Arizona-based First Solar (Nasdaq: FSLR), the world's biggest maker of thin-film solar panels, and California-based SunPower (Nasdaq: SPWRA), which lines up in the U.S. behind First Solar. However, as an indication of the global spread of green fuels, 60% of SunPower is being bought by France's Total (NYSE: TOT), a company that is not usually included with the Big Oil quintuplets, but should be.

The subsidy triumvirate
But what precisely is meant by energy-related subsidies? For starters -- and not surprisingly -- the most pervasive source of federal aid to the industry takes the form of tax credits. Beyond that, subsidies fall into a category that encompasses loan guarantees and other targeted disbursements. A third form of subsidy involves the establishment of a regulatory climate that nudges -- or perhaps directs -- targeted companies or industries toward predetermined approaches.

I find it incongruent that Obama said in his Georgetown speech that "We've known about the dangers of our oil dependence (on foreign sources) for decades. Presidents and politicians of every stripe have promised energy independence, but that promise has so far gone unmet." That comment fails to square with the president's desire to remove the oil and gas industry's benefits from Section 199 deductions.

In its shortest form, Section 199 allows tax deductions for broadly defined manufacturing or production activities. The deduction typically is restricted to 50% of the taxpayer's W-2 wages or taxable income, whichever is lower. Interestingly, the president's budget would remove the deduction from oil companies, but not from those involved in other manufacturing activities. This, in the face of an avowed objective to achieve energy independence for the U.S.

Big bucks for wind and solar
It's also sobering to note the immense disparities among subsidies to the various fuel sources. According to the Heritage Foundation, for instance, solar and wind receive benefits above $23/Mwh (megawatt hour), versus $1.59/Mwh for nuclear, and $0.44/Mwh for conventional coal.

Then there is the relative efficiency, dependability, and staying power of the renewable energy sources, compared with traditional fossil fuels. Let's start with wind, which, to our utter astonishment, can't be expected to blow all the time.

Despite the efforts of such wind power companies as MasTec (NYSE: MTZ) -- which analysts generally favor -- and Broadwind Energy (Nasdaq: BWEN) -- which garners at best a neutral Wall Street reaction -- space considerations remain: In many places, 300 square miles of wind turbines are required to equal the power output of one power plant. Then there are the aesthetic and other difficulties posed by once active, but now abandoned and rusting wind farms.

For instance, such a wind farm was built in 1985 at typically windswept Ka Le on Hawaii's Big Island. Within 10 years, the facility had been rendered an unusable victim of insufficient maintenance. It was sold to California's Apollo Energy, before its transmission was halted by 2006. That experience brought a semirhetorical query from a researcher: "If wind power made sense, why would it need a government subsidy in the first place? It's a bubble which bursts as soon as the government subsidies end."

Thin goes last
As to solar, photovoltaic cells come in three primary types: polycrystalline, monocrystalline, and thin film. The monocrystalline panels exceed the other two in efficiency -- and in cost as well -- given their relatively reduced size and lower space needs.

While Big Oil denizens like Chevron (NYSE: CVX) and ExxonMobil (NYSE: XOM) are beginning to make a mark in solar deployment -- Exxon is doing so in Uganda -- the all-important phrase "grid parity" in the world of solar is achieved in the U.S. only when customers' investments provide a sufficient return, even after government subsidies are eliminated from the cost-benefit equation.

I recognize that renewable energy sources continue to generate considerable optimism from both environmental and cost standpoints in numerous elements of society. At the same time, as Toby and John state in their book, movement into a competitive position with fossil fuels remains decades away when expense, dependability, and environmental considerations are all plugged into comparison equations.

As such, I suggest that, in order to keep abreast of both sides of the energy scene, Fools add both a renewable energy producer such as First Solar and a traditional member of Big Oil, a la ExxonMobil, to their watchlists.

Motley Fool newsletter services have recommended buying shares of Chevron, First Solar, and Total. Try any of our Foolish newsletter services free for 30 days.

We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. Fool contributor David Lee Smithdoesn't own shares in any of the companies named in this article. The Motley Fool has a disclosure policy.