How to determine if 'would' is simple past or past subjunctive here?

Question

Andrew McKillop, author of The World’s Final Energy Crisis, calculates that

✘ (b) China, India and other developing countries will never be able to achieve the vehicle “saturation” ownership levels of the US. ✘

“There is simply no prospect of China, India, Malaysia, Brazil, Turkey, Iran, Ukraine, Mexico and other emerging car producers being able to achieve US, west European, Australian or Japanese rates of car production and ownership,” he says. “At current consumption rates, the estimate of

✓ 3.5bn motor vehicles would increase world oil consumption by about 70%.” ✓

In fact, the petrol used to fuel a car is the very end of a massive industrial process that requires oil at every point. Each car requires up to the equivalent of 55 barrels of oil, and runs on tyres that are about 40% oil by weight, often on tarmac (oil-based) roads. The real volume of oil needed to equip the world with cars is much higher than expected. “Not only is an explosion of the world car fleet a serious threat to the global environment," McKillop says, “but through its impact on oil demand, it will become a threat to international stability.”

Source: http://www.theguardian.com/environment/2005/jun/30/green.travel (featured in LNAT Sample 1, Passage 7, Q4)

I'm trying to determine which sentence, within ✘ or ✓ , is a fact according to the passage. I had thought that ✘ was a fact, due to the use of the simple future 'will', and the verb 'calculates'. Moreover, I interpreted would as a hedge word, expressing doubt/uncertainty. But the answer is ✓. My friend (both our English is basic) claims that would is the simple past of 'will.'

But how does this explain my wrong choice? https://english.stackexchange.com/a/21832/50720 doesn't state that would is a hedge word. Because all subjunctives expresses doubt (among other moods) (About.com for English is too curt), if I'm right that would is past subjunctive, then ✓ is NOT a fact?

Answer 1

All the English modals have a wide range of meanings, and will has a wider range than most, because it is employed as a marker of temporal posteriority; what meaning is intended in any particular instance must be inferred from context.

In this case, the context is provided a) by the future references will never be able and prospect of and b) by the conditional phrases at current consumption rates and estimate. Would designates the future 70% increase in consumption as the necessary future consequence of extrapolating current rates over the estimated future increase in vehicles. The passage might be paraphrased as a frank conditional:

If the number of vehicles were to increase, as estimated, to 3.5bn, this would increase oil consumption by 70%.

It is a past-tense form expressing a ‘remote’ non-past contingency. It is a ‘fact’ in the sense that the speaker regards the consequence as certain if the conditions are met; it is a ‘non-fact’ in the sense that the speaker regards the consequence—and hence the conditions—as impossible of realization, since realization would be intolerably damaging to the environment and intolerably dangerous to international stability.