Jul 26, 2017
the proposal is good,
Jul 26, 2017
Aug 3, 2017
This proposal is excellent. It has the potential to become a real time solution. How about adding "Idling time for deliveries " to the list.
Aug 4, 2017
Idle time is a significant factor in understanding how wasteful so many conventional vehicles are. When the engine is running and the thing isn't moving, efficiency is zero. In an electric, when it's not moving it isn't using any energy. Of course you have to consider powering the AC or providing heat in some cases.
Real life example of what's possible: Yesterday I drove from Savannah to Strasburg, Pa. Total of 714 miles in an eight year old Prius with over 190,000 miles on it. It was a long day with a mix of 80 mph on I95 and bumper to bumper getting around Washington. MPG on the second tank, 48.9. That was with two people in the car and air conditioning on the whole time. One of the reasons the Prius gets such good mileage is because there is essentially no unproductive idling time. Stop at a traffic light or if traffic jams, everything just keeps running on battery, not a gasoline burning engine.
Aug 6, 2017
This is a fantastic idea. Some of the older vehicles we drive daily would be an excellent choice to try this on. The stop and go type of driving we do would be perfect for an electric vehicle that would basically shut down while not moving. Our current vehicles now just keep on burning fuel and is a good reason why we average 4-6 MPG. We have to break our complete dependence on fossil fuels.
Aug 7, 2017
Converting a fleet of vehicles that make short range daily trips makes a lot of sense. I don't see a one size fits all protocol as helpful, except in the most general way. It couldn't be vehicle specific enough. Companies are focused on running their business not worrying about the reliability of a conversion from a company or shop that has maybe done one or two conversions. It would be a hard sell. Targeting specific companies with hundreds of identical vehicles would seem to get the most "bang for the buck". Start with UPS, FedEx or the Post Office. They have hundreds of urban/suburban short routes that use identical vehicles. Focus on these vehicles and possibly enable a conversion company to pitch the idea offering the warranty and support that would be required to make it successful.
Aug 7, 2017
Ron Stevens. Thanks for the comment. You raise several issues that are key to whether or how significantly the elimination of CO2 emitting vehicle drive trains can be accelerated. Agreed, a local shop that has done just one or two conversions will face skepticism about reliability and about the potential payoff in cash savings. There may be a threshold that must be crossed in terms of vehicles completed, before the perceived "engineering risk" is overcome by operational cost savings. That threshold may be twenty conversions or one hundred. Doubtful it would have to be as large as the UPS fleet.
Part of the project, as proposed, is to discover what vehicle would be a good demonstration platform. It might be the UPS delivery van, or it might be the small Ford Transit Connect utility truck. Both of these have relatively short range requirements, and there are many thousands of them on the road.
Regarding warranty and support, creating a company from scratch to do conversions would require funding for a significant warranty reserve. A more promising approach might be expansion into this business by an existing auto service business, for example, an auto parts chain or a muffler shop chain. Both of those will suffer declines in their traditional businesses as EVs gradually become a larger part of the total highway fleet.
Aug 9, 2017
Great idea. This could be a comparably small change for fleet operators without the need to replace vehicles.
Aug 11, 2017
Definitely a good idea, well thought out and comprehensive. To begin by retro-fitting one type of vehicle, trolley or delivery van, and to convert a fleet of them will be a sizeable contribution to cutting CO2 emissions in cities. As an academic project or a business venture, it has great promise toward eventually converting all older vehicles on the road.
Aug 18, 2017
This is true innovation, love it.
All the best for your proposal.
Aug 31, 2017
I suspect that the CoLab entry vehicle conversion will wind up being too expensive because of inadequate battery space in the layout of a gas powered vehicle, but it's worth researching. Vans are likely to have the most space available.
Sep 1, 2017
Thanks David. That may well be the case for some vehicles and some missions.
The trolley example in the proposal very likely will not be constrained. The mission requirement is for a daily range of about 40 miles. With re-gen braking, a 60 kWh battery should be adequate, and provide a nearly 100% reserve. Removal of the conventional engine, transmission, exhaust system and fuel tanks provides quite a bit of usable space for the electric drive, charger(s) and storage battery modules. Additionally, these vehicles are built on a conventional truck chassis. Its a parallel rail structure with roughly two and a half feet of clearance below the floor level. It's a significant void space now that could accommodate battery mounting trays.
As a point of reference, the Proterra Bus Company now offers battery capacity up to 440 kWh. https://www.proterra.com/products/35-foot-catalyst/
The Tesla S can be ordered with as much as 100 kWh of battery energy. http://teslamotorsclub.com/tmc/threads/pics-info-inside-the-battery-pack.34934/ The Chevy Bolt has a 60 kWh battery that's good for 238 miles of range. It's not a very big vehicle.
One other factor about electric drive, that provides design flexibility, is flexibility in the battery pack shape. It doesn't have to fit into any particular shape or be located any particular place relative to the drive motor. The Tesla pack is essentially a pancake under the passenger space. The Chevy Volt has a T shape arrangement of battery modules. The Leaf has battery under the floor and then a section of it that bumps up under the rear seat.
Dec 18, 2017
I have been driving a Nissan LEAF for three years now and love it. The silence, the lack of emissions, and the cost savings are all huge benefits and much enjoyed (also, the car has great low-end torque which makes it a pleasure to drive in stop and go traffic). The driver has to use more care around cyclists who won't always hear the vehicle approaching but they do appreciate the lack of hot, toxic exhaust in their lungs. Tourist buses idle, producing huge emissions, and that problem is fixed by EVs.
Note that if the trial will be done in a place with a winter climate, you should expect half the efficiency from the batteries during the cold months. Not only does the battery pack seem to take longer to charge in the cold, it also takes a great deal of energy to run either the defrosting for the windshield and/or the cabin heat. The LEAF reduces this load in several ways, using a heat pump instead of "toaster" style electric heat strips for cabin heating, and also by including in-seat heat (lovely)! My point here is that your 40 miles out of a 60 kW/h pack will barely be doable in the winter. Maybe the mileage driven by a tourist vehicle in the winter will be less so it won't matter.
Also, for every uphill that "costs" 1.5 kW/h, you can expect the downhill regen to give you 1 kW/h. It is not a 1:1 comparison but no gas car I've ever driven has gotten gas back in the tank as you go downhill :-) and also, the wear on the physical brakes is reduced 75-90% which is also very good for the environment!
I wish you the best and think this is a great proposal.
Dec 19, 2017
Thanks Julia for your very thoughtful comment and for sharing your Leaf experience.
I drove a Leaf for two years and completely agree with your description.
You raise an important issue that I've been wrestling with for some time, how to manage the inside environment of the vehicle during cold weather operations. There are solutions, but they require a bit of a rethink of what comfort really means.
A good starting point may mean considering what it doesn't mean. Being surrounded by 75-degree air doesn't necessarily mean comfort. If you're in shorts and a sleeveless shirt and the air is moving at 25 mph, 75 is chilly. In a room with a lot of other people radiating body heat, it might be warm. Imagine that, if you're wearing a heavy sweater and cords. Point is, what really counts is not the air temperature but rather the rate at which heat is escaping from your body. Get that right and you're comfortable.
Heated seats are a very smart move in that regard. I totally agree on the heat pump for warming the air too. Both ideas may fit for a future trolley design, or for any vehicle carrying temperature sensitive cargo.
In a really cold place though, Cambridge, Mass., for example, a little more boost to warm up the space and its contents may be required. It might be necessary to capture some combustion energy.
In the case of a trolley and some other vehicles, a small fuel burning heater could be provided. These have long been used on aircraft, particularly small twin-engine aircraft. They burn aviation gasoline. If used to boost the output of a heat pump, a moderate trolley cabin temperature environment (60 deg. F) could be maintained while burning a small amount of fuel. Aircraft heaters typically are rated at 35,000 - 50,000 BTU, about a third of a gallon of gasoline per hour, if 100% efficient.
Efficiency of energy use is key. Modern gas-fired home furnaces are now offered at 95% efficiency. Almost all the energy of combustion is captured for it's intended purpose. Quite a contrast with what gets used effectively in a vehicle with a combustion engine, 15% for moving a car, probably less than 10% in a trolley.
More food for thought. The supplemental combustion heater could be hydrogen fired. Could be hydrogen produced by hydrolysis using PV solar electricity.
Jan 12, 2018
It seems like a well-written and logical proposal. While I'm not a mechanical or electrical engineer, but the following issues come to mind:
There should be a big market for retrofitting combustion-engine vehicles, especially as those are replaced in commercial fleets by driverless vehicles (say in about 16 years). Many taxi drivers-owners, truck driver-owners, postal delivery drivers and package delivery drivers are likely to be laid off once driverless cars are phased in, and they may well be interested in the conversions to reduce the ownership cost and allow them to continue working as freelance drivers.
I would also suggest that you study some of the alternative types of batteries such as flow batteries. The goal would to find a battery solution that 1) is less likely to catch fire or explode than a lithium-ion battery; 2) is less expensive than the equivalent lithium-ion battery; 3) is incapable of releasing all of its stored electricity at once, as most commercial vehicle batteries can do (given a conductor and a return circuit); and 4) doesn't require a caustic or toxic liquid to work. From what I've heard, flow batteries such as those being studied at MIT showed be seriously considered. Since vehicles get into road crashes all the time, the goal would to be to reduce the chances for fire, explosion, toxic chemical exposure or electrocution of anyone coming into contact with the damaged power system.
Finally, at least for commercial vans and tractor trailers, the exterior surface could be covered with some form of photovoltaic materials, to provide a trickle-charge to the battery system when the vehicle is in. While many people scoff at the capacity and efficiency of such materials, they are getting better all the time. It might help to extend the range of a vehicle if it was taking advantage of solar loading whenever possible. In this regard, I hope you will consider tractor-trailer rigs, since this would be another large market that might benefit from a conversion kit option (and someone else may already be working on it). The trailer bodies would also present large surface areas, at least on the roof, to collect solar power when conditions are good.
Jan 13, 2018
The proposal is very well written .keep up your work
Jan 13, 2018
Thanks for your contribution to the conversation, Noel. Here are my thoughts on the issues you raise.
Jan 16, 2018
Doing conversions so that they are turn-key for the average person while being safe and reliable will require significant engineering for each and every model and application. People have been doing this for decades and you would benefit from getting input from experienced builders. I feel that this effort is very much underestimated here as far as design and fabrication as well as parts cost.
Jan 17, 2018
Thanks for the comment Gary. I know you have considerable experience in this space and no doubt have a better appreciation for the nuts and bolts of conversions.
That said, I'm not proposing one-offs as the target market. Those were the electric conversions of twenty years ago. Then it was lead-acid batteries, heavy DC motors, probably, and whatever other hardware needed that you could buy at Radio Shack and Home Depot, plus a lot of head scratching and skinned knuckles.
Ten years ago you could buy and drop a 4 kWh lithium ion battery pack into the spare tire well of your Prius and then be able to drive maybe ten miles on battery only. The project wasn't that complicated. Ron Stevens, (see one of the comments above) and I did it in my 2004 Prius. Pretty cool, but there were shortcomings.
Today, entry level for EVs is 100 miles plus range, and the price is reasonable. The point is, a lot has changed over the last two decades, including what is available off-the-shelf in terms of engineering that's integrated into motors, batteries, software and other balance of system components.
The proposal suggests identifying one particular vehicle that has good alignment of mission and the capabilities of existing technology, i.e. battery cost and capacity. Then do a batch conversion so that those additional design costs you refer to are distributed. The trolley example might be ten vehicles for a total cost of $400,000, half of which is balance of system. Balance of system would include engineering and fabrication of components like wiring harnesses and mounting racks.
A logical follow-on would be to select additional vehicles and do batch conversions. Each batch should produce best practice knowledge that drives down the cost of the engineering and design part of the whole package for future batches.One of the beauties of the BEV concept is that the drive hardware can be modular. If 107 hp (original Nissan Leaf) isn't adequate, bolt on a second motor, or a third, just like Tesla. For batteries the same is true.
The trolley sketch example shows, pretty much to scale, 60 kWh of capacity. That should serve the mission well, but there is ample physical space for attachment of more battery modules should longer range be required. Customizing the basic design to make it match the vehicle's mission should require minimal additional engineering design.
I totally agree with your recommendation to capture the wisdom of experienced builders.
Sep 18, 2019
Nice presentation and I concur with judges' award!
Commercial vehicles that make frequent stops, like urban buses, are a great candidate. Working vehicles put more miles/day, they likely accumulate more total miles, and with frequent stops there are significant savings for brake maintenance lower mpg helps make the case for electric, especially when regenerative braking can be included.
This needs to be a "business case" made through a parts supplier, or electric vehicle parts manufacturer, that can reach out through parts dealers. Then just train the "guy at the front desk" to provide reliable supply AND reliable guidance to mechanics.
Interesting: check WrightSpeed hybrid turbine electric configuration, which would accept a range of fuels, including renewable ("drop in") fuel, e.g., biofuel. The firm started with garbage trucks in Bay area but the extensive fleet to be retrofit changed hand, next to NZ to retrofit a bus fleet, though it appears the system was not entirely ready for "prime time." The concept requires ~1/8 the batteries, claimed to reduce liquid fuel use 67% or more, and is claimed to reduce PM 90% below a EURO5 diesel. See > http://tramways.weebly.com/electric-bus.html