How do you make a Toyota Prius even greener? Make it a Plug-In...
My test Prius was the first of my 2011 test vehicles that I could plug into my ESB Electric Car house socket. The plug-in hybrid is one of just three currently in Ireland for evaluation purposes; they go on sale to the public in 2012.
So apart from having a plug socket on the nearside front wing, what else is different from a standard Prius? Basically, the Prius is still a conventional Toyota Prius Hybrid (see our archive), so it has a modest petrol engine, an electric motor and some rechargeable batteries stored behind and under the rear seats that combine to give the car similar performance to an average family car. Fuel consumption figures are impressive, too, and similar to a modern small diesel or stop/start petrol engine.
The plug-in element is an additional stand alone set of batteries in the boot floor that is recharged by domestic mains electricity via a standard three-pin plug. These additional batteries on their own give Prius Plug-In 20km of electric vehicle (EV) range at up to 100km/h. In the real world (or should I say mine) this meant I could do a two-school run in EV mode using just the batteries charged from the wall at my home. When that power is exhausted (a dash display green plug socket symbol goes out) the Prius continues to work the same way all Prius do.
The upside with Prius Plug-In is the extra 20km of EV ability. So if you only do tiny city mileage you may never need to use the petrol engine. Plus if your electricity is charged on a night meter then you will be truly quids-in, as they say.
The downside is also the 20km! It's a bit of effort for such a small return, especially if you do any sort of ordinary motoring. There is a cable to be connected from the car to the wall socket and this can be a bit of a pain in bad weather or if the ground is dirty. Coiling up the thick, black cable is also a chore and a bit risky for those who are dressed for the office or to impress. I found myself more than once for convenience sake leaving the cable connected to the house.
As for ease of use, Prius Plug-In can and was connected to the wall by my seven-year-old and he could also get the air conditioning to heat up the car in the morning using the mains electricity by simply pressing the A/C button on the keyfob.
During my week with the car I did 600km, including one trip to Kilkenny from Wicklow. Overall, I averaged 4.7 litres per 100km in petrol consumption. I used EV mode 13% of the time behind the wheel and at my green best just a few percent higher. City dwellers can expect a higher percentage of EV use.
The driving experience and display technology is an early adopter's delight - one forward gear, one reverse, regenerative braking etc. Bluetooth audio and other gadgets help, plus there are loads of digital display options that tell you how economical you're being and more importantly many whales you've saved... Okay, that's a slight exaggeration.
Is Prius Plug-In ready for 2012? No, but it is getting there. It needs greater EV range and a simpler more efficient cabling system - maybe a retractable one like a forecourt's air line could be a solution (royalties please Toyota to the usual address!)
Well done Toyota for leading the way, and I'm sure the final 2012 car will be worth a closer look.
Michael Sheridan
