While technology holds much promise for enhancing our ability to find，develop and deliver there resources to consumers，I believe it also has an important role to play when it comes to protecting the planet.We all recognizethat mitigating the negative impact that energy production and consumption has on the natural environment is becomingincreasingly impor tant，and represents another vita l imperative for suppliers，consumers，policymakers，regulators and other stakeholders.Whatever our professional role or discipline，or the position we occupy along the energy value chain，each of us has a part to play in lightening energy"s environmentalfootprint，and in making it possible to balance our responsibilities toward the environment with our commitments to the economic prosperity and wellbeing of our communities and their inhabitants.Achieving that balance is among the most significant challenges facing our planet today，and underscores not only the work of the Harvard University Center for the Environment，but also my remarks this afternoon.
So，where do we go from here？Well，when it comes to energy，the immediate future looks a lot like the recent past，with hydrocarbons continuing to account for the lion"s share of energy supplies.In fact，fossil fuels will remain the bedrock of energy supplies for both the US and the wider world for many more decades to come，through the use of oil in transportation via significantly improved conventional engines，hybrids or eventually in hydrogen production；and with coal and gas when it comes to electric power generation.
The EIA also projects that renewables，including hydroelectricity，will be generating more energy over the next quarter-century.But even with anticipated technical advancements，that source"s share of global energy supplies will only increase by one percent over the next 25years，from 8percent of total supplies at present to 9percent by 2030.When we look at alternative energy，we find that sources such as ethanol are beginning to play a growing role，while hydrogen and fuelcells still have some way to go before they are viable in the market，and face a numberof technical and commercial obstacles that needs to be resolved.
However，this is a process that will take time，and because of the complex，multifaceted nature of the obstacles that alternatives still face，this is not a transformation that can be rushed.We also have to recognize that thespeed of adoption will vary considerably around the world，given each nation or region"s relative resource base，economic model，level of energy intensity，degree of technological sophistication，and sunk infrastructure costs.Just as different countries have vastly different levels of things like mobile telephone penetration or automobile ownership，in my judgment various markets around the globe will adopt and adapt alternative fuels at markedly different rates，and only slowly begin to converge over time.
Because we face a future in which we will need energy derived from all sources，and since it will take some time for alternative energy to expand its contributions to global supplies，I think we also need to look more closely at the major sources of our energy supplies for years to come.In short，the sources that will make the most important contributions to the energy mix in the near-to medium-term must receive a suitably high priority when it comes to research and the development of technological enhancements.If we ignore the energy supplies that will matter most over the coming decades-and yes，oil is a prime example-we may inadvertently undermine both the environmental and economic goals this nation and the global community have set for themselves.