Powering the Tesla Roadster with 'Green' Electrons

Dr. Rob Wilder is CEO of WilderShares LLC and manager of the WilderHill Clean Energy Index, the first Index/Fund on Wall Street for renewable energy, better energy efficiency, and zero-carbon solutions. He is also a Lecturer at University of California, San Diego, and was previously on faculty at University of California, Santa Barbara, and University of Massachusetts. Dr. Wilder has been an AAAS/ EPA Fellow in Environmental Science & Technology, Fulbright Fellow, and National Academy of Sciences Young Investigator. He is widely published and has sat on various boards, such as the marine section of the Society for Conservation Biology. He resides in a solar-powered home in Encinitas, Calif., with his lovely wife, Diana, and their two children.

I’m a long-time car nut, and so it’s not surprising I’m already in love, sight unseen, with the Tesla Roadster. I reserved one myself after doing due diligence, and now eagerly await its arrival. My wife and I decided the Tesla Roadster makes sense for us in large part because it changes not only how EVs are regarded, but how the future of all cars is viewed as well.

We’re solar powered at our home and thus already make “green fuel” for the Tesla Roadster; we enjoy integrating neat zero-carbon solutions into our family’s home, and now into our cars too. We feel it is important to help to drive down costs so EVs grow more affordable. Plus, it’s simply great fun to apply solutions, all the while powering our home – and cars – without oil.

Wilder family solar panels: Thermal
panels in foreground heat pool
water while monocrystalline panels on
the house produce electricity.

Over the years my family and I have become passionate about solar power (photovoltaics, or PV) and clean technologies. We have a pretty large 6.5 kilowatt (kW) PV system with lots of luxuries and so live well. We also have two large solar thermal water heating systems, use energy efficient LED (light-emitting diode) and CFL (compact fluorescent lamps ) lights as well as passive shading, and generally think about energy use. We have untapped wind resources and so may add more clean power in the future.

We have two types of PV to make “green” electrons. One has 21 monocrystalline solar panels on our roof for 3.85 kW, linked to a 3.5 kW inverter. The other has 24 polycrystalline panels that are ground-mounted, rated 2.8 kW, and run to a 2.5 kW inverter.

Given this solar-home, I’ve long felt if I could just find an excellent two-seater EV to plug into these electrons, as I’ve now found in the Tesla Roadster, there’d be lots of advantages over ordinary, undesirable and slow “gasoline-powered cars.” With the Tesla Roadster, we will get a car with great performance and it is an “American-Fueled Vehicle,” which feels great as a matter of patriotic pride.

There are also neat aspects that follow from the Tesla Roadster being powered to some degree by solar as a "green fuel." If I charge the Tesla Roadster at home in the daytime, then my house is strictly being a power producer pushing electrons out into the grid, and so I’ll know these are purely solar-made green electrons. I think this is the most elegant fuel of all.

Even if I happen to charge in early evenings or when it’s cloudy with a mixture of “green” and “brown” (from the grid) electrons – or if I regularly charge at night with only “brown” electrons generated by natural gas-fired plants or out-of-state coal plants – those big thermal plants are still the considerably more efficient way to power a car than gasoline.

Additional electricity is produced using
ground-mounted polycrystalline panels. The
Wilders maintain their own website that
tracks solar energy produced.

In the future, having an EV plugged in at home raises intriguing additional possibilities. Because we make our own power, we’ve switched our utility connection here to Time Of Use (TOU) metering. TOU is common in solar homes. It simply splits the day into two periods: one when electricity is cheap, from 6pm to noon, and the other when it’s more expensive, from noon to 6pm weekdays. This means we’re “paid” much more per watt for surplus power we generate in daytime, when in essence our meter spins backwards due to a shining sun, than we pay for the watts of power we have to consume at night. That peak coincides brilliantly with peak solar power, so our house is credited more richly for surplus daytime juice put into the grid.

An electric car is based around a large mobile battery and if that car is built with Vehicle to Grid (V2G) capability, it could also feed power back into the home. Potentially home-owners could arbitrage the difference between low cost for power of around 5 cents per kWh available at night when most plant capacity is just sitting idle – and the much more dear costs for electricity during the peak of day at maybe 15 cents or more per kWh. By charging up at night when juice is cheapest and being able to just regularly sell back into the grid by V2G, or if a signal sent from the Utility calls for it, an EV that’s simply sitting there plugged in to the garage can be a money spinner for the home owner.

While I imagine cars from Tesla Motors won’t have V2G capability for a few years, it might not be too far off. Today’s lithium ion batteries have rather limited cycle life, so it wouldn’t make sense to hasten a demise of those costly batteries for small nightly profit gains (a hardware issue). But batteries are improving quickly, and the software obstacles can be overcome. Plus Utilities will likely be very supportive, just as they are with notions of Plug-in Hybrid Electric Vehicles becoming new home power sources and new customers too.

With coming batteries and the utilities onboard, it’s conceivable that future EVs, including this fantastic Tesla Roadster, will typically have V2G. We innovative Americans just need to put our minds to it and treat energy as if it matters. It’s hard for me to overstate the significance of the Tesla Roadster as an agent of elegant change.

The Wilder family

Back here today in our own home, we have a simple but fun web-based live system that monitors our ongoing energy demand, and charts it against our solar output. This helps us to be smarter in the ways we use power. In the future, in a rather similar fashion, there might be an optional uplink allowing a Tesla Roadster owner to review the day’s energy use from driving, and chart that against battery performance and even solar green fuel output. On the other hand, it’s something that one could simply ignore and just have the delight of driving, but being in touch with your power source can sometimes be fun!

In my career I’ve tried to help bring academic theories about clean energy solutions to real world applications. For instance, I launched with a colleague a WilderHill Clean Energy Index based on concepts like solar power, wind, energy efficiency, better batteries, ultracapacitors, superconductors, fuel cells, etc. To me, the lovely Tesla Roadster reflects in undeniable ways how when fast-emerging technologies are put together well, the sum is far greater than the parts.

Part of the beauty of the Tesla Roadster is it puts to rest the tired argument that electric cars must be ugly, undesirable, or golf-cart like. The Tesla Roadster is simply a better car, and it proves EVs don’t have to be slow and inelegant like typical gasoline-powered cars.

I think this Tesla Roadster is about to change everything – not just how we think about EVs, but how the future of cars is viewed. Plus, plugging it into our solar powered house and just driving on “green” electrons is simply going to give me endless enjoyment, at least when I can wrestle the car away from my wife!