In an e-mail to the company’s staff last week, van der Veer said soaring population growth and rapid economic development meant that, “easily accessible supplies of oil and gas probably will no longer keep up with demand.”

With conventional supplies inadequate, there would be no choice but to add other sources of energy, he said.

“Renewables, yes, but also more nuclear power and unconventional fossil fuels such as oil sands. Using more energy inevitably means emitting more CO2 at a time when climate change has become a critical global issue.”

Van der Veer outlined two scenarios for the world’s energy future.

The first scenario is called “Scramble”.

“Nations rush to secure energy resources for themselves, fearing that energy security is a zero-sum game, with clear winners and losers,” van der Veer wrote.

“The use of local coal and homegrown biofuels increases fast. Policymakers pay little attention to curbing energy consumption – until supplies run short.

“Likewise, despite much rhetoric, greenhouse gas emissions are not seriously addressed until major shocks trigger political reactions. Since these responses are overdue, they are severe and lead to energy price spikes and volatility.”

Under the alternative scenario, “Blueprints”, sees international political cooperation leading to harmonisation of efficiency standards and taxes, a convergence of policies on emissions trading and local initiatives to improve environmental performance of buildings.

“Cap-and-trade mechanisms that put a price on industrial CO2 emissions gain international acceptance,” Van der Veer said.

“Rising CO2 prices in turn accelerate innovation, spawning breakthroughs. A growing number of cars are powered by electricity and hydrogen, while industrial facilities are fitted with technology to capture CO2 and store it underground.”

Climate change calculations made at the Massachusetts Institute of Technology indicate that a Blueprints world with CO2 capture and storage results in the least amount of climate change, provided emissions of other major manmade greenhouse gases are similarly reduced, according to Shell.

The company regularly uses scenario-planning to test the likely impact of widely divergent economic and political scenarios on its long-term strategy. It says both scenarios are equally plausible but it expressed a clear preference for the Blueprints path.

“We will know only in a few years whether December’s Bali declaration on climate change was just rhetoric or the start of a global effort to counter it,” van der Veer said.

“Much will depend on how attitudes evolve in China, the European Union, India, and the United States. The Blueprints scenario will be realised only if policymakers agree on a global approach to emissions trading and actively promote energy efficiency and new technology in four sectors: heat and power generation, industry, transport, and buildings.

Van der Veer’s email was reported on RoyalDutchShellplc.com, an independent website that monitors the company.

www. RoyalDutchShellplc.com