Update: Video from Steve Fambro in the Aptera 2e at TED.

US 1549 made an emergency landing in the Hudson River last week after encountering a flock of geese. This is not the first time that a commercial jet aircraft has landed in water with no fatalities. Past examples include Pan Am Flight 943, which ditched in the Pacific Ocean between Honolulu and San Francisco in 1956 after running out of fuel, and Japan Airlines Flight 2 which mistakenly landed in San Francisco Bay during heavy fog.

While Toyota has yet to reveal the details of the new Prius, educated guesses have formed with increasing fervor over the past several months, deduced from a variety of sources like spy shots of camouflaged vehicles, official sneak peeks provided via a viral marketing campaign, analysis of improvements in related vehicles, and more. Owing to these sources, here are three of the anticipated changes that I’m looking forward to.

Prius Sunroof The new Prius with factory installed sunroof open.

Sunroof and Solar Panel

One of the many fantasized additions to the Prius over the years has been the addition of solar panels on the roof of the car to augment the power that is currently provided to the electric motors, directly or indirectly, by the gas engine. Keen modders and enterprising companies have attempted such additions to existing vehicles over the years. While technically possible, the unfortunate reality is that such setups can realistically provide only a handful number of kilometers per day, making solar powered propulsion in the Prius little more than a curiosity. Additionally, having solar panels on the roof of the vehicle seemed to run against those who desired having a sunroof on the Prius.

Prius with Sunroof and Solar Panel

Surprisingly, the new Prius is expected to sport both solar panels and a sunroof. However, the solar power will not be used to propel the vehicle. Instead, it will provide power to the climate system to cool (and warm up?) the interior. On the current Prius, the air conditioning and heat augmentation units both run off of the hybrid power system (so that they can run with the gas engine off), sapping precious energy that could otherwise be used to move the vehicle. Rather than trying to use the relatively little solar power to move the vehicle a few kilometers, directing the energy to the climate system seems like a sound choice, that should lead to gas savings by reducing energy demands on the hybrid system.

Exhaust Heat Capture

The Prius features a parallel hybrid setup that allows either the electric motors or the gas engine, or both simultaneously, to drive the car. One of the fuel saving techniques the vehicle employs is to shut down the gas engine when possible, such as at a stop light, or during times when the 50 kW electric motors can move the car without assistance from the gas engine. However, for the gas engine to shut down, it must first be within its full operating temperature range.

To help the gas engine reach operating temperature quickly, the Prius features a thermos that stores engine coolant when the vehicle is shut down. The idea is to store the hot engine coolant so that it can be used to help warm up the engine the next time the vehicle is started.

While it’s easy for the engine to reach its optimum temperature in warm to hot climates, the same is not true in colder conditions or for short drives. From my personal experience, anything below 12°C holds a challenge. Not only does the vehicle have to contend with cold ambient temperatures, but turning on cabin heat also drains heat from the engine core. Although the Prius features two electric heating elements in the lower vents, they can only augment the heat flowing into the cabin; the car is primarily dependent on the engine core for cabin heat. Also consider that when the engine does finally reach full temperature and shuts down, cold air can quickly cool it back down to the point where it needs to start up again.

Air Vents in the new Prius

The new Prius is expected to feature an exhaust gas recirculation system, similar to the new Lexus RX 450h. The general idea is to capture some of the heat in the engine exhaust to warm the engine coolant so that the engine itself can be warmed up much more quickly. The press release about the improvement in the RX 450h claims that, “at −5°C on a typical driving pattern showed that the engine could be stopped a full 1 000 seconds (over 15 minutes) earlier than the previous model.” If this holds in real world driving, it should mean dramatically better hybrid performance in cold climates.

Enhanced EV Performance

The current Prius is capable of driving at up to 64 km/h on the electric motors alone. After that, the gas engine must spin, whether power from it is needed or not, due to the rotational limits of the electric motors. The 228 cells of the Prius’ hybrid battery can only store enough power to move the vehicle about 4 km or less without assistance from the gas engine. The current Prius is generally not designed to be used as an electric-only vehicle.

With the new Prius, the top speed for electric motor operation is expected to increase to 100 km/h, and the hybrid battery will also receive a corresponding increase in capacity of up to double the current capacity. Together, these changes should allow the vehicle to operate in electric only mode in more situations, and also be able to store more energy from regenerative breaking at high speeds or during long downhill stretches.

Energy Monitor in the New Prius

While, these changes will not dramatically change the way the car operates immediately, they lay the groundwork for a plug-in hybrid electric version of the Prius. Toyota is known to be testing plug-in hybrid electric versions of the current Prius at various locations, including the University of California at Berkeley and Irvine last year. A press release yesterday notes that Toyota plans to, “start global delivery of 500 Prius PHVs powered by lithium-ion batteries,” in late 2009. Enabling the Prius to be operated as a plug-in hybrid electrical vehicle (PHV) opens up the option to power the vehicle from clean and renewable energy sources, such as wind and solar. It is not known at this time what driving range a lithium-ion powered Prius will have.

Want to Know More?

The next generation Prius will be unveiled tomorrow at 11:30 AM (EST), at the North American International Auto Show. The Toyota website has a countdown to the unveiling of the third generation Prius. And, you can join the PriusChat community, who will undoubtedly be following the announcement and dissecting the details of the vehicle as soon as they become available.

Full Moon Rising A full moon rises over Cochrane, Alberta. The moon is currently at its orbital perigee around Earth, making it appear bigger and brighter than usual.

The moon’s orbit around Earth is elliptical, varying its distance to the planet. It is currently at perigee, the closest point in its orbital path to Earth. Science@NASA has a brief article about tonight’s full moon.

Update: The Twitter status blog says they’ve identified the cause and blocked it. Everyone should check their email settings and password.