I'm driving a 2018 Prius Prime (plug-in). What do you want to know about it?

[MetroMPG]

Originally Posted by Vman455

Does the Prime include electricity consumption in its onboard fuel economy reporting?

Answer is NO.

I just drove the car from full to empty on battery power, and the fuel consumption stayed at zero until the gas engine fired up.

That said, it has a separate gauge for electricity efficiency. It doesnt combine them.

This was my first highway trip with the car. I babied it and went 46.7 km (29 miles) on the battery in less than ideal conditions: cool (9C = 48F), breezy & rainy. Back roads/scenic route cruising at a target speed of 75 km/h (47 mi.). Mostly cruise control, with some DWL on hills.

Total trip was 95 km, so just under half on electrons.

MPG gauge said 1.7 L/100 km = 138 mpg US at the end.

[MetroMPG]

Oh, and that's with 1 mod in effect: I pumped up the tires to 50 before I left.

[MetroMPG]

I drove it at night for the first time, and can confidently say this car has the best headlights I have ever had the pleasure to sit behind. Holy cow! The low beams are fantastic. The high beams are otherworldly. Sharp, bright, focused, white light. Who knew?



Generally I avoid driving at night if possible. Having lights like these could change that.



It makes driving the Metro/Firefly/Miata feel like they're equipped with candles behind glass. What can I retrofit on them?? Need moar candlepower!

[Vman455]

And they're quads, upping the cool factor!

I've got factory quads on my car now--I bought a set of OEM LED headlights, which have two projectors each side for the low beams instead of the single projector I had retrofitted before. Double the fun.

[MetroMPG]

Fun MPG anecdote!

I had a chance to drive both cars over the same route over the weekend: Similar ambient temperatures, but weather conditions were actually worse for the Prius (drizzle, wet/damp roads, breezy).

On gas, the Prius reported 3.0 L/100 km = 78 mpg US over ~95 km.

That's driving with load (DWL), most of the time on cruise control, on the back roads/scenic route, with cruise set at 75 km/h (47 mph) most of the time.

In the Metro, I only managed 3.3 L/100 km = 70.5 mpg at similar speeds.

The Metro's ScanGauge is calibrated pretty accurately. I don't know how accurate the Prius' factory gauge is, but even if it's off by 10%, it would still be even with the Metro, in worse conditions.

Amazing, considering the only mod on the Prius is 50 psi, and the Metro has bags of mods on it.

Even more amazing considering the difference between the 2 cars in comfort, quiet, power, convenience features, safety features, etc., etc.

[mpg_numbers_guy]

Did the Prius start out with a full battery? How full was the battery before vs. after? Those numbers seem a bit high for the Prius - maybe while the battery is full the car will be more generous with the battery and make the car appear more efficient than it is.

[MetroMPG]

The EV-only portion of the battery was depleted. The ICE fired as soon as the distance to empty on the EV ranve gauge hit zero.

[Vman455]

Another question, if you noticed: once the EV range is depleted, will the Prime turn its engine off up to 84 mph, or does it then default to the non-plug-in's 62 mph engine-on? (If you ever went that fast on this loop!).

[MetroMPG]

Sorry - I didn't get going that fast on this trip.

One thing I noticed is even on the highway, this car spends a lot more time engine-off than my 2004 Prius did, which I think spun the engine (whether using fuel or not) at anything higher than around 46 mph, if memory serves.

[redpoint5]

Originally Posted by Vman455

Another question, if you noticed: once the EV range is depleted, will the Prime turn its engine off up to 84 mph, or does it then default to the non-plug-in's 62 mph engine-on? (If you ever went that fast on this loop!).

I doubt it. My Gen III plug-in will shut the engine off below 44 MPH when the EV range is depleted as long as there is sufficient battery charge and not much power is needed. The engine comes on above those speeds regardless. With a full EV battery, the car will go up to 62 MPH with the engine off.

At 84 MPH, the power requirements great enough that running the engine is efficient.

I would be curious what the max speed on the Prime is to shut off the engine when the EV range is depleted.