Clean Energy in California

Day 4: Electric Vehicles, Demand Response, and Exergy
by -- April 14th, 2012

The morning of day 4 was a whirlwind of presentations by several key industry players: Better Place, EnerNOC, and Lawrence Livermore National Laboratory.

Better Place: Innovative Solutions for Electric Vehicles
Andrew Lee walked us through a plan to accelerate the transition to electric vehicles. Most of the talk these days is about the vehicles themselves – what kinds of batteries they’re using, how far they go, pure electric versus hybrid – but Better Place wants to shift the conversation to focus on how to make electric vehicles affordable, convenient, scalable, and “future-proof”.

They are doing this through a set of services for the owners of electric vehicles: batter lease, battery switching stations, and a charging network.

To make EVs more affordable, Better Place maintains ownership of the most expensive part, the battery. They lease a battery to the owner for a monthly fee, which significantly reduces the upfront cost of the car.

Because Better Place owns the batteries, they have been able to develop a clever solution to running out of juice. Pull up to your local battery switching station and a robot in the floor switches out your battery for a fully charged one. You’re off and running with no wait for a charge.

Finally, Better Place plans to develop a network of charging stations at homes, offices, and public spaces to better serve their customers. Drive to work or the mall, plug in your car, and you’re ready to go when you come back.

These services are just getting off the ground, so keep an eye on Better Place, they’ve got big ideas and they’re not afraid to use them.

EnerNOC: Energy Management with “Killer Apps”
A “killer application” is a function that is so important, even indispensable, that you would purchase a technology just to be able to use the application. For example, finance professionals flocked to computer stores with the development of various spreadsheet software types in the 1980s. The computer was worth the high price just for that one piece of software.

Well demand response is the killer app of smart grid, and David Meyers and his team at EnerNOC are taking that very seriously. The ability to shed load at a moment’s notice to maintain the reliability of the grid makes the development and deployment of a successful smart grid well worth the effort. Demand response can be used to abate the intermittency issues of renewables, especially wind. Wind speeds are variable and seasonal, and the wind doesn’t always blow when we need the electricity. Demand response via the smart grid would allow utilities to use extra electricity generated at night by a wind facility to cool a refrigeration facility colder than it needs to be – like freezing ice cream to -20 instead of -10. Then we have thermal storage in the ice cream, which can be used when we need it.

Thermal storage in ice cream might be a bit of a silly example, but it really drives the point home of what we could do with an integrated national smart grid network.

Lawrence Livermore National Laboratory: Exergy
AJ Simon spent the majority of his presentation on one of the most complicated diagrams I have ever seen. It was a Grassmann Diagram of exergy. Exergy is the work value of any unit of energy. While energy can never be created nor destroyed (thank you, thermodynamics), exergy is ever decreasing. But, lucky for us, we can get more from the sun.

AJ did a fantastic job explaining how the exergy from the sun and exergy already on the earth intertwine to make, well, everything we consume – food, energy, stuff, and waste. But everything stores exergy differently. For example, the amount of uranium needed to run a 1000MW power plant for one day would fit in the trunk of a Toyota Corolla. To run the same size plant on coal we would need about 86 train cars full of coal. There is a huge amount of energy expended getting all of that coal out of the ground and to the power plant, and that is not usually part of the conversation.

I wish I could explain as eloquently the details of exergy. What I can say is that AJ’s main take-away is pretty simple. The “three-legged” stool of energy should be comprised of a “seat” of energy efficiency with three supporting “legs”: nuclear, renewables, and fossil fuels. None of them are perfect, but together they make a feasible energy future.

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