As climate change has increasingly become the most pressing issue of our generation, sustainability presents the kind of opportunity we're especially excited about at GV: a problem of global magnitude, and solutions that require both creativity and engineering.

Since sustainability is a cornerstone of investments I make at GV, I'm very excited about the work Kathy Hannun is doing. She is one of the brightest and most innovative minds in the alternative energy space. As co-founder and president of geothermal pioneer Dandelion Energy, Kathy envisions a world where home heating and cooling will be affordable, energy efficient, and good for the environment. As she says, "In the future, when people look back, combusting a fuel inside your house will seem like a weird thing to do." I'm excited to continue investing in Dandelion with the company's latest funding round announced today.

In the future, when people look back, combusting a fuel inside your house will seem like a weird thing to do.

Dandelion started as a Google X project, where Kathy began her career. "My title was 'Rapid Evaluator,' which meant that I was always looking for new ideas. We experimented with things like turning seawater into fuel. I was hungry to find an idea that was ready, something we could launch tomorrow. That's when heat pumps started capturing my attention."

Geothermal works through the exchange of heat between the house and the earth. Dandelion drills 300-500 feet below a house and connects a ground loop to a geothermal heat pump. In the winter, heat from far underground warms the house, and in the summer the system works in reverse to push warm air out of the house into the ground. This process is four to five times more efficient than traditional systems, and Dandelion estimates every home that adopts geothermal is the equivalent of taking 39 cars off the road for a year.

"When we started," Kathy recalls, "there were no drilling techniques or rigs built for home geothermal. Everyone was using the same type of rigs that were digging water wells, and they couldn't even fit in people's yards. Right off the bat, we created a suite of drilling equipment that could access suburban yards, and we worked with a manufacturer that could scale to homeowners. That shaved off costs from the beginning."

Kathy brings this type of inventive thinking to everything she does. Named by Fast Company as one of their Most Creative People, she believes "the challenge of nurturing creativity is finding the balance between the humility of recognizing that there is wisdom built into the way things are done today, but also the confidence to question all those assumptions. A lot of commonly held assumptions are incorrect. If you err too much on either side of that spectrum, it's very hard to be creative."

As a leader, Kathy gives her team a lot of freedom. "I state the problem that we need to solve, voice my support and excitement, and provide resources. Sometimes your solution won't pan out, but giving people the freedom to run through that process always pays off. You practice, you persist, you gain skills, and you become better. Jumping into the deep end is a great way to learn how to swim."