Energy is more than a hot-button topic for policymakers and business leaders -- it represents a real resource crisis.

Global energy needs are expected to increase by 56 percent over the next 30 years, with much of that increase coming from booming cities. The energy needs of urban dwellers are not only unique, they are massive: estimates show that cities could account for up to 80 percent of global energy usage by 2040.

This increasing demand stands in stark contrast to the traditional balances of energy production and consumption in large industrialized nations. The United States, for example, has consistently consumed more energy than it has produced. According to the U.S. Energy Information Administration, energy production in America was relatively stagnant between 1995 and 2004, never surpassing a yearly growth of 2.44 percent. But that trend is starting to reverse course. But after two consecutive years of relatively strong increases -- including a massive 4.4 percent surge in 2011, the largest single-year uptick in 27 years -- the U.S. is starting to close the gap on the consumption imbalance and carve a path forward.

What’s powering this positive trend? Incredibly innovative energy solutions, which are helping ensure that our global energy supply remains viable, efficient, and sustainable. Here are just a few of the cutting-edge technologies and innovations that hope to pave the way toward energy stability worldwide.

How can we ensure that energy in cities is sustainable?

As our world grows, cities are too -- millions upon millions of people will be packing into urban areas over the next several decades. In response, energy companies and urban dwellers are utilizing new sources of power and integrated facilities, which can capture energy that was previously wasted and put it to use. Some cities, like Fort Collins, Colorado, are taking this concept even further: producing more energy than they consume.

What will make maintaining solar panels more cost efficient?

In particularly sunny areas, like the deserts in the western U.S., solar panels can be a highly successful mechanism for harnessing the sun and converting its rays into renewable energy. But the costs associated with installing and maintaining the panels often prevent municipalities from investing in the energy source. To combat these expenses, a number of companies have developed robots to clean the miles of panels required to generate substantial electricity. Dirty solar panels, especially if covered with sand and silt, can reduce photovoltaic efficiency by about 30 percent. Here's where this new class of robotics comes in, which promise to cut costs and save man-hours by increasing the viability of solar power investment.

How can collecting wind power be more effective?

Traditional wind turbines are about 260 feet tall and are rarely more than 50 percent efficient. But imagine a new class of wind turbines that are much larger and can capture and convert winds up to 1,000 feet in the air. This new type of wind power benefits from high-altitude winds, which are much stronger -- up to eight times more powerful than lower altitude winds -- and allow for a significant output of wind energy. Currently, companies are developing state-of-the-art buoyant turbines that can float high in the air and is are not limited to an on-the-ground construction.

What can energy companies do to more reliably store and reuse energy?

One significant problem with renewable energy is that storing the generated energy is costly and practically unreliable. One company, however, is addressing the challenge by building a machine that uses surplus energy from renewable sources, and using it to compress a special mix of air and water. SustainX, the developers of the machines, says that when demand for energy is high, the compression is released to spin electricity-generating turbines. The company hopes this sort of energy storage -- cheap, reliable, and environmentally friendly -- will allow for additional alternative and renewable sources to flourish.

How can we safely recycle nuclear waste?

For decades, the U.S. has been burying nuclear waste deep in the ground, often without consideration for potential radioactive leaks and other environmental risks. Californium, a radioactive element first discovered in 1950 at the University of California at Berkeley, may help solve the problem of safe storage. Because Californium is able to bond with each of the discrete elements of nuclear waste, scientists are seeking to build waste containers out of this element with the hopes that the Californium will separate the components of the waste and allow the fuel to be purified and reused.

This week, we’ll be discussing, analyzing, and sharing more big ideas like this during the 2014 Aspen Ideas Festival. Follow along with us here and on Twitter throughout the week.