Energy investment consultant Chris Nelder takes issue with my suggestions for upping transportation efficiency as a way to reduce the demand for offshore oil, saying they would “do absolutely nothing” to eliminate the need for risky deepwater drilling projects.

In fact, he explains why a lot of oft-proposed green solutions aren’t going to do much good. Smart land use (which I also plugged) won’t remove the need for oil, he says. Nor will transit-oriented development, telecommuting initiatives, a cash-for-clunkers redux, or more efficient driving. Electric cars won’t make a difference any time soon. The Senate’s American Power Act won’t do enough. Solar and wind can’t scale up fast enough and require all sorts of new grid infrastructure.

“To replace our offshore oil with wind, you’d need 195 Californias, or 74 Texases of wind, and probably 20 years to build it,” Nelder writes at Huffington Post.

“Our challenge is far more difficult than most people imagine … Scale and time-to-market issues bedevil most of the typical Green alternatives.”

The pessimistic piece notes the inadequacy of nearly every policy and technology that’s touted as a solution to our national energy dilemma. Nelder focuses on the peak-oil problem and the risk of offshore drilling, though his point applies to global warming too: none of these policies or technologies are going to solve these problems in the time we need them too. If we do them all at once … the numbers still aren’t in our favor.

The particulars of Nelder’s post are fine. What rankles me is the argument that because we don’t yet know how to finish the task of kicking oil use (and, more broadly, eliminating greenhouse gas pollution), we should despair before we even start.

My hunch is that building a nation that runs on clean energy is going to be both easier to start and more difficult to finish than the general public expects. At the beginning of the energy quest are efficiency and land-use steps that bring all sorts of side benefits. Compact, walker-friendly neighborhood design improves public health and cuts taxpayer spending on road and pipe maintenance. Better-insulated buildings save money, drive down the need for new coal plants, and cut ambient air pollution that causes illness and disease.

Once we seize that low-hanging fruit, choices become more difficult, particularly around nuclear power. But I don’t see the point in harping about the endgame, playing the role of an expert discourager, when we’ve barely begun with the no-brainer steps. Let’s get started first.