The Green Geek

How green is the Tesla Roadster?

Officially unveiled 4 days ago, the Tesla Roadster has gained significant attention from the media, as well as sports car enthusiasts and environmentalists everywhere. With it’s very sporty 4 second acceleration, sleek design and reasonably high top speed (135mph), it’s no surprise why the car enthusiasts like it. It’s also all electric and has no emissions, which is the biggest reasons environmentalists like it, but how green is the Tesla Roadster?

The Tesla Roadster uses 6,831 lithium-ion battery cells, a sophisticated computer system to maintaining charge balance, and a safety system that can disconnect power if a safety issue arises. The Li-Ion cells are fully recyclable, and the higher storage density of these batteries gives it about 3 times the range of the late General Motors EV1. The Tesla Roadster takes about 3 hours to charge from the home charging station, and an optional remote charging system is available for charging it away from home.
Many of the critics of electric vehicles state that EVs aren’t pollution-free, they simply shift the pollution to a coal power plant which generates the electricity for the consumer’s home. This is a valid comment, but may not be accurate depending on several other factors.

Although 55% of the United States power is derived from coal power plants, there are many other possible sources of electricity available from local utilities, such as wind and solar. Drivers of the Tesla Roadster may also have the option of powering their cars with their own solar panels; Tesla Motors chairman Elon Musk has said that the company is working to provide buyers with home PV panels, making the Tesla Roadster a net producer of energy as well as being completely emissions-free.

Even if the consumer’s power comes from a coal-fired plant, this doesn’t mean that there has to be excessive pollution. Certain controls can be implemented at the power plant to reduce emissions. In addition to the conventional stack scrubbers and electrostatic precipitators to sulfur and remove fly-ash, a novel new technology is being developed by a company called GreenFuel that which algae to remove carbon dioxide and nitrous oxide from stack emissions. The stack gases are bubbled through the algae tubes, as the algae soak up the carbon dioxide and oxides of nitrogen they sink to the bottom, to be harvested. The algae can be processed to produce biodiesel as well as ethanol, however this technology can also be used to achieve carbon sequestering; the algae can be used as a beneficial soil additive instead of being processed and burned.

Going even further, there’s no reason that coal plants need to actually burn coal. The hoppers, combustion chambers and boilers work just as well with other forms of biomass, such as Giant Miscanthus. Burning grass-based biomass in coal power plants would result in a carbon-neutral cycle, and if the GreenFuel algae stacks were included, the carbon dioxide could be re-used to make biodiesel and ethanol or put back into the soil to enrich it. Solar and wind are far more efficient than biomass though, the only reason that biomass would be a viable option is it’s easy to grow grass, and we already have many power generation facilities capable of using it. Forget “clean coal”, run the power plants on biomass until we have large scale solar available.

Continuing advances in battery technology will also improve on both the distance EVs can travel, as well as shorten the charging time. Other technologies like nanotechnology-enhanced capacitors could even replace batteries, holding a large amount of energy, but also charging in a matter of seconds or minutes rather than hours. I believe the best course of action in the short term is plug-in hybrid electric vehicles followed by pure electric vehicles. Plug in hybrids would be able to make use of the existing fueling infrastructure, but also use all-electric mode for short trips. In addition, PHEVs can run on algae generated ethanol, further reducing their environmental impact.
The Tesla’s price tag of $100,000 will make it unavailable to most people, however the demand for electric vehicles is there, and the constantly-improving technology is available now; unlike hydrogen fuel cells which seem to perpetually be “10 to 15 years off”. The Tesla Roadster has the potential to be very green, and will also stand as an inspiration for other electric vehicles in the future; including some with a slightly more managable price tag.