ROCHESTER, MINN. — Most of the talk at the Mayo Clinic's 2011 Transform Symposium this week has been about ways the health care system of the future can leverage technology to better serve patients. Even the informal conversations I've had have been around this theme — I shared a cab Monday to the convention with a designer working on a gadget that would allow parents to give their children remote ear examinations with a tiny, otoscope-like device attached to, you guessed it, a smart phone.

But the future brings more than opportunities for improved technology and better ways of doing business — there are also sobering challenges, a point that British designer and writer John Thackara drilled home Tuesday morning during a discussion about how projected declines in energy production will dramatically transform the health care system.

Citing a 2010 report by the U.S. Army's Joint Operating Environment that projects potential shortages in oil supplies as early as 2015, Thackara argued that health care providers will soon need to find ways to care for patients with drastically fewer energy resources. The prospect of declining oil production — a phenomenon known as Peak Oil — will pose an especially tough challenge to an industry that's so heavily reliant on oil-generated products like drugs, supplies and devices, he asserted.

"We should be preparing for a health care system based on 5 percent of the energy we have today," Thackara said.

What that will mean for large providers like the Mayo Clinic isn't clear — a fact Thackara noted during his speech, pointing out that large hospitals usually consume four times as much energy delivering care as they do on simply maintaining the energy needs of the buildings they use.

 "This great, glorious machine runs entirely on fossil fuels," he said.

While a hospital forced to use just 5 percent of its current energy output sounds like a doomsday scenario, Thackara said there are some signs of hope, noting that there are ways of providing health care with markedly fewer resources than are currently consumed. He singled out Cuba, which achieves similar health outcomes to the U.S. with around 5 percent of the total cost.  And while that might not the best comparison for U.S. providers, Thackara noted that population health initiatives, like the Alzheimer 100 project in his native England, can achieve impressive outcomes with considerably less energy-intensive interventions than that of an acute care hospital.

"All over the world are examples of people looking after their health and others' health with little or no cost," Thackara said.  "Five percent health runs on metabolic energy, not fossil fuel energy."