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We all know that our hybrids are more efficient than a gas only car, but have we really thought about why? I believe that understanding why will make all of us more efficient drivers. There are 3 main ways that our hybrids increase efficiency over a gas only car: Driving in EV modeTurning off the ICE when not neededRegenerative BrakingI will examine each method and how it increases the efficiency of the car. Driving in EV mode Given that all of our energy comes from gasoline, why is driving in EV mode better than driving with an ICE only? The answer can be found from examining the EPA ratings for PHEVs or BEVs. The MPGe ratings of these vehicles are often around 100 MPGe combined, with numbers as high as 120 MPGe in city driving. So, what is MPGe? Saying that the Fusion Energi gets an EPA rated 108 MPGe city means that on 33.7 kWh of electricity a Fusion Energi can go 108 miles on the city test cycle. 33.7 kWh is the amount of energy contained in a gallon of gasoline as measured in kWh. Each gallon of gas contains 125,000 BTUs, or approximately 31,000 calories if we think about it as a source of energy like we measure food. 125,000 BTUs equals 33.7 kWh of electrical energy. Why are the MPGe ratings so high? Electric motors are much more efficient than gasoline engines. According to the Dept of Energy (http://www.fueleconomy.gov/feg/atv.shtml) only about 15% of the energy in each gallon of gas is converted into kinetic energy in city driving and about 26% in highway driving. Using an electric motor to provide propulsion means that about 60% of the energy is converted into kinetic energy according to the Dept of Energy (http://www.fueleconomy.gov/feg/evtech.shtml). This is why driving in EV mode is better and why PHEVs and BEVs can drive much farther on a lesser amount of energy. The battery pack of the Nissan Leaf stores less energy than is found in a gallon of gasoline and can still carry that car almost 100 miles between charges. The C-Max Energi and Fusion Energi store 6.5 kWh of energy in the battery to drive about 20 miles; that is equivalent amount of energy to 1/5 of a gallon or 24.7 ounces of gasoline. With that tiny amount of electrical energy those cars can go farther because an electric motor is much more efficient. Electric motors do not waste as much energy as heat losses compared to an ICE. They are also not affected by varying atmospheric conditions since they are not using air to initiate combustion. Since as much as 75% of the energy in a gallon of gas is converted to heat energy by the ICE this is a big advantage for the electric motor. What does this have to do with a hybrid? Our cars do not plug in to an outlet to charge and get EV only driving, but they do run for upwards of 50% of the miles in the city using only the energy stored in the battery. This means that when we are running in EV mode we are seeing much higher efficiency than if we were driving an ICE only car. When designing a vehicle the ICE must be large enough to provide sufficient power for maximum acceleration conditions. This means that the ICE is much too big for everyday driving and that there is a lot of inefficiency when running an ICE with a low power demand. The hybrid turns the ICE into an electric generator by artificially increasing the power demand when driving with the ICE to a level where the ICE is more efficient. Hybrids also include a smaller ICE that is able to more often run at its peak efficiency. This means that the car is most efficient in EV mode at lower power demands, and more efficient running the ICE under higher power demands. For us to maximize our EV mode driving and our fuel economy we want to use EV mode as much as possible when the power demand is low, and use the ICE when the power demand is higher. Turning off the ICE when not needed Since our cars can turn off the ICE when it is not needed we don’t waste fuel idling unnecessarily. When decelerating there is no need for the ICE to run and burn gas, yet in gas only cars it does. When stopped there is no need for the ICE to run and burn gas, yet it does in gas only cars. This doesn’t mean that we can sit and leave our cars turned on for long periods while stopped because this will use up the hybrid battery and make the ICE come on to generate electricity. Regenerative Braking Another big inefficiency with gas only cars is braking. Brake pads and rotors turn momentum into heat energy, effectively wasting that energy. The regenerative braking system in our cars seems to recover about 70-80% of the kinetic energy the car has when we begin braking. That is a huge improvement over the 0% recovered by traditional friction brakes. This helps our efficiency in city driving. Driving conditions for peak efficiency Based on the above information we see that for peak efficiency we want to accelerate using the ICE, then back off once reaching cruising speed and use the electric motor to maintain our cruising speed. Since the electric motor’s efficiency advantage over the ICE is highest at lower power demands we see the highest results at lower speeds in the city. At 25 MPH the power drawn from the battery to maintain that speed is minimal. I’ve cruised for miles without using the ICE when cruising at 25 MPH without stopping. This is the logic behind the hypermiling technique known as DWB (driving without brakes). The DWB technique involves trying to drive in a manner than you brake and stop as little as possible. While braking is much more efficient in our cars than in a gas only vehicle, it’s still better to brake as little as possible since an electric motor only converts 60% of the electrical energy stored in the battery into kinetic energy and regenerative braking only converts 70% of the kinetic energy back into electrical energy. For example, 1 kWh of electrical energy pulled from the battery would only get you 0.6 kWh of kinetic energy and the 0.6 kWh of kinetic energy would be converted into 0.42 kWh of electrical energy back into the battery through regenerative braking. It is much better to use that 1 kWh to drive 5+ miles without stopping than it is to stop and only recover 0.42 kWh of electrical energy. There are certain routes I have found where I can consistently get better than 60 MPG because I don’t have to stop very often and I can maintain a constant rate of speed. Such routes are the pinnacle of efficiency for a hybrid. I imagine that on those same routes I could get 75 MPG out of a Prius and over 130 MPGe in a C-Max Energi or Fusion Energi.

I want to take issue with Ford's marketing of the Fusion and C-Max. Just like in Who Killed the Electric Car? it talks about how the automakers didn't really educate consumers or advertise the electric vehicles we see the same thing today with hybrids and PHEVs. If Ford really wanted to sell the Fusion Hybrid/Energi and C-Max Hybrid/Energi they would target their marketing at people who weren't previously considering hybrids/PHEVs and show them the advantages of these vehicles. But, they don't do this. Ford only advertises the C-Max as a Prius killer trying to convince people that it is better than the Prius. If you were not previously considering a Prius then this advertising is wasted on you. Also, many people have a negative image of the Prius in their mind, linking the C-Max with the Prius in advertising is not going to sell C-Maxes to those people. The Fusion Hybrid is advertised like a footnote at the end of the regular Fusion commercials and nothing is done to tout the benefits of the Fusion Hybrid in comparison with the gas Fusion. Also, where is the advertising for the Energi models??!? I have seen nothing other than the banner on Ford's website that occasionally displays the C-Max Energi and Fusion Hybrid when going to Ford.com. There is a scene in Who Killed the Electric Car? that mentions how GM went about contacting people who were interested in buying the EV1 and telling them all the limitations of the vehicle and then proceeding to claim that no one wanted it. Nowadays there is not enough done to advertise the benefits of buying a Fusion Hybrid over buying a Fusion EB. There appears to be ZERO advertising about the benefits of buying an Energi model over buying a gas only vehicle. This is very disappointing. A few months ago I made a comment about how I'm not convinced that Ford really wants to sell these cars because of how they had to know that there would be an uproar about the real world fuel economy. I don't think that the engineers, marketing people and executives at Ford are so stupid that they didn't expect some backlash for building a car to ACE the EPA tests that would thus perform worse for many people in real life. When regular cars that are not built to ace the EPA tests often perform worse in real life for some drivers and better for others there is no way that Ford could have thought that what they did wouldn't cause an outrage from disappointed consumers. It seems that just about all consumers are disappointed. Experienced hypermilers are unable to exceed the EPA ratings in the Ford hybrids like they can in other hybrids. Regular consumers are getting much worse than they expected. And even I am a bit disappointed. I tried to not expect better than 47 MPG overall, but when our past cars have all done better than EPA estimates consistently it is hard to not expect that this car will also exceed those numbers. Sadly we're at 42.1 Lifetime on the dash and have found the city mileage to be more than 47 MPG but the highway mileage to be worse. And I am a bit disappointed. Cognizant of how consumers would react, I question how much they actually wanted to sell the cars...looking at the advertising I also question how much they want to sell the PHEVs. If we think about it, the hybrids and PHEVs and BEVs hurt the Ford dealers. Since we need to change oil less often in our hybrids than a gas car, that costs the dealerships money and costs Ford income from selling parts. Since we need brakes less often we also bring in less long-term revenue. A PHEV is even more extreme with the lack of oil changes and a BEV has no oil changes period, and no other routine maintenance associated with an ICE. This makes me worry that maybe the automakers have engineered the batteries to fail at a certain point, say 100,000 miles since that is beyond warranty outside of California, and then they're hoping to make up this lost revenue replacing battery packs. Since we're driving the first year of cars with a NEW battery pack design who knows what changes have been made. The old NiMH packs were proven to last a long time, but we don't know that about the Li-Ion packs yet. This makes me nervous. I'm not a conspiracy nut, but I try to be realistic. This whole world is corrupt. The system is broken. And who's to say that this isn't going on... Your thoughts?

As we near the release of the updates I was thinking it would be good to know who exactly on the forum is willing to get the update first and share their results. If you're willing to get the update first and report back on your results please say so below. My idea is to then create a topic for each user who gets the update early on so that each person can individually report on their results, independent of what other users might say. Also, while we all love sharing our personal experiences and reading those of others they don't always add a lot of value. So also please comment below any ideas you have of more scientific tests that we can do to see the effects of the update. Ideally the guinea pig volunteers would run the tests before the update and then again after the update. Please don't use this topic to discuss the update or say things like "I'm not going first!" as that can be done here. Thank you.

http://www.theatlantic.com/magazine/archive/2013/05/what-if-we-never-run-out-of-oil/309294/?single_page=true Very fascinating article, it's a little long, but worth the read. As hybrid owners we have all shown ourselves to be somewhat energy conscious and this is a very interesting take on the worldwide energy situation

Here is an article from Edmunds about the future of the ICE and EVs. It is very heavily biased in favor of gasoline. http://www.edmunds.com/car-reviews/features/why-the-internal-combustion-engine-is-the-future.html This link is a critique of the Edmunds article by Green Car Reports. http://www.greencarreports.com/news/1083696_yes-combustion-engines-will-be-with-us-for-decades-howeve