Bill Joy of Kleiner Perkins. Credit: Russ CurtisFORTUNE -- Having helped both create the Java progra...

1. Bill Joy: Better batteries key to Green power adoption
Bill Joy of Kleiner
Perkins. Credit: Russ Curtis
FORTUNE -- Having helped both create the Java programming language and co-found Sun
Microsystems, Bill Joy is best known as a technologist and entrepreneur. He hopes to add
environmentalist to that list.
As a partner at leading venture capital firm Kleiner Perkins, Joy is devoting much of his time to
overseeing Kleiner's portfolio of nearly 60 green start-ups. He spoke at Fortune's Brainstorm Green
conference about what green technologies he believes are most likely to work, and why.
Joy is a believer in wind, or perhaps more accurately, micro-wind. The big problem with wind power
to date, he said, is that small windmills cost far more per watt generated than do large wind farms
with giant turbines and huge blades--sometime ten times as much. "The smaller wind gets the more
expensive it gets," Joy said.
That gap can be closed, or at least greatly narrowed, Joy argued, just the way that better technology
http://energy.gov/eere/office-energy-efficiency-renewable-energy allowed microprocessors to replace
mainframes, shrinking the physical computer and the cost of computing at the same time. FloDesign,
a company that Kleiner Perkins has backed, has used a new design based on airplane engines,
fundamentally changing the aerodynamics and, Joy says, the economics.
That company's product won a design award for and earlier version of product three years ago, but
despite the slow development Joy remains jazzed on the potential.

2. A pair of Joy's other green goals: "The ability to
store and retrieve electrons at low cost [and]
the ability to make them distributed and
cheap."
If consumers can generate cheaper wind or
solar power on their own property, he said, the
next key will be matching that power with
when it's actually needed. That means better
batteries. "The grid moves things in space,
batteries move things in time," Joy said.
Again the problem is scale. Systems to store
green power by pumping water uphill then
releasing it to generate power when its needed
work in industrial settings, but not in a private
home. Joy sees a few different viable options
for personal power storage.
The first small-scale option is using compressed air to store and release wind energy advantages
power, Joy said. Another: build a cheaper twist on today's lithium ion batteries. The trick, he says,
is building slightly larger batteries than you'd find in a laptop and using water as the electrolyte.
One green disappointment for Joy: a failure to build a breakthrough desalination process that could
cheaply turn seawater into drinking water. The stumbling block he said, is that there so far has
been no way around using heat to power the process. "Anybody who's worked with hot salt water
knows how corrosive and nasty a thing it is."
Joy is still optimistic about water purification technology. With the desalination dream on hold, he
has devoted more effort to reclaiming "used" water, which might come with more bacteria than sea
water, but doesn't have all the nasty salt.
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