Let’s be kind to the Fossil Free campaign and simply call it idealistic, rather than naive.

The nationwide student campaign to press colleges and universities to divest from fossil fuel investments isn’t getting much traction. Administrators at several top schools, including Harvard, Brown and Cornell, have rejected Fossil Free’s demands.

Most schools haven’t taken a position, but Fossil Free says about 15 have said no. Only eight have said yes, and none of them are large schools with big endowments.

Fossil Free is missing its mark, and here’s why: Big energy has been a good investment. Coal, oil and natural gas drive the global economy; they remain in high demand and have been reliably profitable.

By contrast, renewable energy — biofuels, wind and solar — have generally been poor investments. Many took government grants and then went belly-up. Experts say it will take decades of research and development to completely replace fossil fuels with alternatives that actually return a profit.

Nonetheless, that day eventually will come. Steady improvement in the alternative energy sector is the second-greatest enticement for colleges and universities to reassemble their energy portfolios.

The greatest enticement is Marcellus shale gas, an industry growing rapidly in Pennsylvania and other states, thanks to new technology enabling collection of the gas from deep underground.

Even now, transportation businesses are converting their fleets to burn the plentiful, cleaner and cheaper natural gas. And in the not-too-distant future, emerging hydrogen fuel cell technology will generate electricity, heat and air conditioning to homes using less natural gas than current home heating units use. The fuel cell technology already exists; the challenge now is to make units smaller and more efficient — in other words, to make it a profitable investment.

The rapidly growing shale gas industry is pressuring OPEC, the Mideast-centered cartel that supplies nearly 30 million barrels of crude oil every day.

OPEC’s dozen member nations are meeting today in Vienna to discuss shale gas and other challenges to their livelihood. The cartel’s dominant member, Saudi Arabia, says it intends to maintain current production levels in spite of falling demand in the face of increased shale gas production. That means oil and gasoline prices could fall, particularly if any OPEC member breaks ranks and increases production.

Meanwhile, ongoing strife in Lybia has cut its daily production from 1.5 million barrels to about 250,000 barrels, presenting an opportunity for an OPEC state to ramp up production.

Internally, Saudi Arabia is fighting off a challenge from Iran and Iraq to replace Saudi’s Abdullah El-Badri as secretary general, the equivalent of OPEC’s chief executive officer, a challenge that reflects more instability to come.

OPEC’s turbulence and shale gas competition make petroleum in particular, and fossil fuels in general, a risky long-term investment. But the industry, for the time being, is necessary — and that’s why many universities and colleges have rejected Fossil Free’s appeal.

And Fossil Free remains focused on the environmental principle of its campaign, without much regard for the geopolitical and economic tensions surrounding the energy industry.

Fossil Free would be wise to adopt a more realistic long-term strategy, one that recognizes a conversion to sustainable energy alternatives won’t happen overnight. A more reasonable strategy would reward Fossil Free with “maybe” responses from colleges and universities, and fewer flat-out “no’s.”

—T.A.H.