Category Archives: Electric Vehicles

The Hybrid Tipping Point

One of the questions I often get asked about my car is, “Is it all-electric, or is it a hybrid?” For most EV owners, the answer to that is easy, but for the BMW i3, it’s a bit more complex. You see, it is a hybrid in the sense that it does have a petrol engine, but it’s also completely different from most of the Toyotas, Mitsubishis, Hyundais, etc. out there.

The i3 has a ‘Range Extender’ option (known as the REX), which is a little 650cc scooter engine, not much bigger than a melon, and a two-gallon petrol tank. The engine never drives the wheels directly, and in fact, it doesn’t even really recharge the battery, but it can keep the battery at a constant level of charge while you’re buzzing along. So if I have a battery range of 70 miles and I need to go, say, 120 miles with no charging points en route, here’s what I normally do: I put my destination into the satnav, and then glide silently out of town and onto the motorway. When my battery has depleted to about 50%, I turn on the REX, and use a bit of petrol until the remaining satnav distance is less than my remaining battery range, at which point I turn it off again. This means I only get the (small amount of) extra noise on the highway, where there’s plenty of other noise anyway, I keep pollution away from the populated areas, and I arrive silently at my destination, having used the minimal amount of petrol.

For me, it’s the perfect combination. I’ve now done about 12,000 miles in this car, and I’ve used less than 12 gallons to do so, which means my average MPG is still in four digits. In 5-10 years’ time, we’ll have much bigger electric ranges, without having to pay Tesla prices, and charging points will be sufficiently common that the petrol bit will be unnecessary. (Unless I move to a remote part of Colorado or Australia, I think I have probably purchased my last fossil-fuel-burning car.) At some point between now and then, one of the major petrol companies is going to install rapid chargers on all their forecourts. There’s a rumour that it might be Shell. This will be a brave thing to do, because it will instantly make EVs massively more attractive to the ordinary driver and will make a dent in the revenues of all the oil companies. On the other hand, this process is inevitable, so you want to be the company that does it first. I watch with interest…

But let’s get back to the hybrid discussion.

The challenge that plug-in hybrid designers face is how wholeheartedly to embrace the battery. You see, there’s a tipping point: you can’t sit on the fence. For most hybrids, you are building a normal car, and adding all the cost, weight and complexity of batteries and an extra motor. You don’t get enough electric range to use it as a real EV, though you might get some pretty impressive MPGs if, say, you charge each night and have a short commute. But when you’re running on the battery, you’re dragging around a lot of unnecessary metal and liquids. When on petrol, you’re carrying a lot of heavy battery. You need to keep a big enough engine to do everything people expect of a traditional car as well as fitting in a big enough electrical system to make the battery bit worthwhile. Minimalism it ain’t.

The beauty of pure electric vehicles, in contrast, is just how simple they are: no gearbox, exhaust, piston rings, tappets, crankshafts, oil sumps, filters, radiators, fuel-injectors, spark plugs, catalytic converters… all that messy stuff just goes away. I had originally planned to get a plug-in hybrid; the Golf GTE caught my eye when it came out, and I enjoyed test-driving one of the first ones in the UK, but I’d been spoiled by that point, because I’d also driven a couple of proper EVs, and I realised that they had to be the future. I often tell people that if you have (a) another car and (b) a driveway on which to charge, there’s no real reason now, when choosing a second car, for it not to be all-electric. The Nissan Leaf or Kia Soul EV are great vehicles, and I started to think I could get something like that for my normal day-to-day use and park my old Golf out of town somewhere, to be fetched when needed for long treks.

But for us, it would be silly to have two cars, which is why the i3 was the perfect solution. All the benefits of an EV, with no ‘range anxiety’ and very little extra complexity. Unfortunately, in Europe at least, BMW are currently the only company making this combination, which means that to get it, you have to pay BMW prices: quite a change for someone like me who spent much of their life crawling under elderly Minis or Beetles. I hope some other manufacturers catch on soon, but in the meantime, I do at least get the satisfaction of driving what Munro Associates described, a couple of years ago, for a whole range of reasons, as “the most revolutionary car in terms of creative engineering and manufacturing since Henry Ford’s Model T”.

Altruistic Autonomous Vehicles

One of my shortest recent posts generated quite a lot of discussion, both here and on Facebook. I wrote:

When we have proper and affordable self-driving vehicles, will that be the end of the railways?

Clearly there are some things that railways will do better for the foreseeable future, like long-range high-speed links, or carrying heavy freight. And don’t get me wrong: I like train journeys. But it seemed to me that the key reasons people currently take trains for normal day-to-day journeys — wanting to read en route, a lack of parking at their destination, avoiding congestion — could very soon be overcome when, for example, your car can go and valet-park itself after dropping you off at the office.

And the disadvantages of train travel: the fact that instead of going from point A to point B, you have to go at least from point A to point B to point C to point D, possibly waiting on a cold platform at point B for an indeterminate period, and not being sure whether you’ll get a seat from point C to B on the return journey. Will it be worth the hassle?

One of my assumptions is that traffic congestion will become less of an issue when cars are smarter, of course, which may not be a valid one, especially if lots of train travellers take to their cars instead.

There’s an interesting question as to whether lots of small independent agents trying to meet their own goals are going to result in an optimal solution for road congestion as a whole. We may start off with vehicles that are pretty autonomous initially, but become less so in due course, as the road infrastructure starts to adapt to them. Network packets on the internet know their destination, but it’s the routers (the junctions) that tell them which exit from the roundabout to take.

Will the Department of Transport manage overall use of the network better than each individual car? Well, that depends on who has the better computer scientists, of course! But it also depends on the amount of knowledge each vehicle can get about the overall road network, and, of course, on how selfish your car is: will it decide that the needs of the many outweigh the needs of the one (or the few)?

Perhaps we need Altruistic Autonomous Vehicles? (You heard it here first!) There could be financial incentives to encourage this. You get lower road tax if your car agrees to obey centrally-prescribed rules at times of high congestion. Perhaps you get to use the high-speed autonomous-only lanes if you’re willing to hand over to the cloud-based algorithms. Of course, this could open up all sorts of wonderful opportunities for hackers, too. Remember the movie?

Anyway, perhaps congestion will be less of an issue, but for a completely different reason. If you can be having a coffee, working on your laptop and taking Skype calls while you slip quietly along in your electric car, you may be more productive than if you’d got to the office on time.

Car Talk

The Amazon Echo arrived in the UK a couple of days ago, and by combining some of my earlier work with John Wheeler’s excellent Flask-Ask framework I was able to make it talk to my electric car.

Also available on Vimeo here if preferred.

Counting the cars on the new electric turnpike

IMG_2598In the last couple of months there’s been a lot of discussion amongst electric vehicle owners in the UK about Ecotricity’s decision to start charging for its ‘Electric Highway’: the network of rapid charging points at motorway service stations and similar locations. Some think it’s outrageous that, if you’re charging away from home, it can cost as much per mile as petrol. Others point out that these charging points cost many tens of thousands to install and run, and the cost is therefore very modest. Personally, I think they have the pricing about right, but I wish they’d chosen a 15-minute granularity instead of going for 30-minute slots. But no doubt this will be tweaked over time.

One benefit of these chargers no longer being free is that there are fewer ‘casual’ users, or people hogging them for extended periods of time. If you turn up at a charging point now you’re very likely to find that it’s available, something that is, in fact, exceedingly important. (The ideal charging network is one that nobody else seems to use except you! It’s quite a contrast to petrol pumps, where the owners want them to be in use almost constantly.) However, this change is so apparent that some have speculated that almost nobody is using the pumps, and the whole idea is a disaster. The real numbers were, however, pure speculation for anybody outside Ecotricity.

Well, with some devilishly cunning technical tricks, I came up with a way to monitor a few charging points and see how they’re actually being used. I tried to pick a mix of some popular pumps, some I was just personally interested in, and some in more out-of-the-way places, so I settled on the charging points at:

  • Cambridge Services (A14)
  • Baldock Services (A1M)
  • Heston (M4 near Heathrow)
  • IKEA Wembley
  • South Mimms (A1M/M25)
  • Leicester Forest East (M1)
  • Kettering (A14/A43)

And I checked them every 5 minutes for 4 days – a Fri, Sat, Sun and Mon – to see whether they reported their status as ‘Available’ or ‘In Use’.

Kettering, sadly, appears to have been out of action for all this time, as does one of the pumps at Baldock. And one of the Leicester Forest pumps was reporting ‘Swipe card only’. So for this (small and completely unscientific) trial, I effectively had 6 locations and a total of 12 charging stations. And here’s what I found:


Click for a higher-resolution image, or download the PDF here

Each dotted horizontal line represents a normally ‘Available’ pump and the vertical marks indicate when it is ‘In use’. The five minute period of my checks mean that a standard half-hour charge is shown by roughly six little vertical lines.

A few points to note:

  • Some of the sessions are less than half an hour, and some appear to be noticeably longer, though my system wouldn’t detect one car finishing and another immediately taking its place as two separate events.
  • Drivers who get their home electricity supply from Ecotricity do not pay for charging, so they have no particular incentive to work in half-hour units. The majority of sessions, however, are multiples of half an hour.

Here are some numbers derived from the data:

Approx pump statistics

ID Location Samples in use/total Avail% 24hr Avail% >7am 30min sess/day 30min sess.p.a.
1037 Leicester Forest East Services 102/2292 95% 93% 2.1 780
1038 Leicester Forest East Services CCS 94/2286 95% 94% 2.0 720
1068 South Mimms Services 0/2294 100% 100% 0.0 0
1069 South Mimms Services CCS 141/2291 93% 91% 3.0 1078
1080 IKEA Wembley 462/2263 79% 73% 9.8 3577
1081 IKEA Wembley CCS 219/2291 90% 86% 4.6 1675
1132 Heston Services 292/2291 87% 85% 6.1 2233
1133 Heston Services CCS 54/2294 97% 97% 1.1 412
1134 Heston Services CCS 30/2294 98% 98% 0.6 229
1235 Baldock Services 253/2294 88% 85% 5.3 1932
1236 Baldock Services CCS 0/0312 100% 100% 0.0 0
1241 Cambridge Services 0/2294 100% 100% 0.0 0
1242 Cambridge Services CCS 246/3433 92% 89% 3.4 1255

Assume electricity cost per session of £1.44
Annual profit from these pumps approx £63348
From a network of 300 pumps, if these are representative: £1461881

With the exception of the Wembley IKEA points, you can turn up between 7am and midnight and have at least an 85% chance of finding one of these free.

Now, these pumps may not be representative, being generally rather London-focussed, especially since a couple of my more rural ones didn’t yield useful data. I’ve included one which was offline and excluded a couple of others. And all of my figures are very approximate, so should all be taken with a big pinch of salt. But my estimate is that Ecotricity are making £1-2M per year from the network at this rate.

In their announcement about the introduction of the charges they talked about having provided £2.5 million pounds worth of free travel in the first five years of the network. It grew from nothing to its present size over that period, so we might assume that the annual costs of about £0.5M represent the half-way stage and that they were getting close to £1M p.a. at the end of the free period. I don’t believe these numbers include the substantial installation costs of the pumps, which are apparently around £30-50K each. Nor, I think, do they include the salaries of support staff, etc.

But overall, my analysis, for what it’s worth, would suggest that the current charges are not too wide of the mark for what they need to run a sustainable network. It won’t make much profit nor allow much further development, but nor will it run at a huge loss, as it has up to now. Fortunately Ecotricity have a variety of motivations for this work, and not all of them are profit-based.

I could attempt a more substantial analysis, but the APIs I was using are probably not meant to be public and I didn’t want to trespass on their good will. If anybody from Ecotricity would like to authorise me to capture more data (or offer me a job to keep me quiet!) I’d be delighted to talk!

The network will need further investment, since the number of electric vehicles on the road is growing fast. This is offset somewhat by the fact that their electric range is also increasing, so charging points are needed less frequently. But analysts are predicting surprisingly short timescales for us to reach the point where the majority of our cars are electric, so it’s a fascinating space to watch…

Software security and the new app platform

As regular readers will know, my car has a programming interface which, sadly, is not officially supported by BMW. Still, it lets me create some little apps to improve the daily experience of car ownership; not something I’ve really been able to do with any previous cars. We’ve come a long way from some of my earliest ones, where I spent most of my time straightening bent carburettor needles and replacing leaf springs!

car_lock_checkMy latest hack is a little script which runs periodically on one of my servers and checks whether the car has been stationary for more than 15 mins. If so, and the windows, sun roof or doors are open or unlocked, it sends a notification to my phone. This is partly for security reasons, but mostly because the British weather has been sending us hourly alternate bursts of sunroof-opening heat and torrential downpours! Of course, if I’m not near the car at the time, I can lock it remotely.

One of the many things I find appealing about the move to electric cars is that the actual mechanics become so much simpler. I no longer have an exhaust pipe, a clutch or gearbox, an oil sump or filter, head gaskets or piston rings. The motor isn’t much larger than a melon, and the batteries can be made in various shapes and sizes to fit the layout of the vehicle. In my case, I have a flat floor, with no propshaft tunnel or gear lever to get in the way. Reconfiguring such a design to be a van, a campervan, a flatbed truck, or whatever, is much less of a challenge now.

As the complexity of the mechanics goes down and the flexibility goes up, I think software, both inside and outside the car, is going to play an ever more important role in our experience of it.

The automotive industry has become interesting again, for the first time in many decades.

Archers 2.0?

If I had a farm, I’d want one of these. Actually, I don’t have a farm, but I still want one of these.

Petrol? Where we’re going, we don’t need petrol…


As regular readers will know, a couple of weeks ago I took my electric car to the Lake District with my friend Hap. I go there fairly regularly, but this was the first time since I got the i3, and I was wondering how it would cope. Charging points are fairly scarce there, and the gradients very different from its normal home in East Anglia. Would we get stranded somewhere on the Whinlatter Pass?

In fact, I needn’t have worried. Our charming B&B in Grasmere let us plug in each night, and even though we did a fair bit of driving around, we always came back at the end of the day with more than 50% charge left. In truth, though you can spend a lot of time driving there, the distances are usually fairly small because so much of it is below 30mph (something which also helps the efficiency!) The steep uphill slopes swallow battery but this is offset somewhat by the regenerative braking on the steep downhill ones.

What I hadn’t expected was just what a delight the car was to drive there! This was partly because creeping down valleys and winding over mountain passes is much more pleasing in an almost-silent vehicle (though you do need to watch out for walkers in the middle of the road who haven’t heard you coming). It was partly because it loves the corners, as a BMW should. And it was partly because the big windows and high driving position gave such a good view of the landscape.

But it was mostly because of what i3 owners call the ‘single-pedal driving’: the fact that the regenerative braking kicks in as you lift your foot off the accelerator, meaning that under normal circumstances you very rarely need to use the brakes. If you know the Lakes, you’ll know there are many roads where, in a normal car, you need to move your foot from accelerator to brake on every corner. You need to change gear around every second bend. I, on the other hand, was just gliding around the corners and up and down the hills with my foot on the one pedal. No gear changes (I don’t have a gearbox, even an automatic one). No sound of straining engines, because it doesn’t make any sounds. No need to engage low gear for engine braking on the steep slopes, because engine braking is what I do all the time. I even enjoyed the long descents, because they recharged my battery.

No, all in all, I spent a lot of time grinning as we drove from Grasmere to Borrowdale, from Great Langdale to Coniston, from Tilberthwaite to Ambleside. It’s the best place to drive this car, and it is certainly the best car I’ve ever driven there.

In Arcadia ego

My friend Hap and I drove from Cambridge to Grasmere today — 280 miles — using about a pint of petrol. It should have been all-electric, but we got lost trying to find one of the charging points!

You may or may not think that having to visit rather more M6 service stations on the way than one might otherwise do makes such a form of transport worthwhile. But I think you’d agree that paying about £1 each, to cross the whole country to a place where you can do this walk before dinner, is pretty good value:



Hiking into the future

Today I realised there was yet another reason why I want a self-driving car.

It’s for when I’m walking.

The challenge with going for a good long walk in the country is often finding a nice circular route that will bring you back to where you parked the car.

But imagine you didn’t have to do that. Imagine that you could just walk from point A to point B and the car would be waiting for you when you arrived. You could then ride home in comfort, or, perhaps, enjoy lunch from the picnic hamper in the boot before setting off for the next reunion at point C. You could do this for days.

What’s even better is that you wouldn’t need to know your destination in advance! You could wander lonely as a cloud, floating o’er hill and dale, until you spied a welcoming tavern. While enjoying a pint of their finest ale, you would summon the car, and it would be parked outside by the time you wanted to leave. (And take you home, of course, if the ale had been particularly fine…)

The end of an era? Or the start of one?

IMG_2439Early yesterday morning, Richard and I set off to drive from Cambridge to Sheffield for a business meeting — my first such trip in my electric car. It’s 260 miles there and back, and I’ve done longer journeys, but this was the first where professional courtesy was contingent on the state of the UK charging network.

Fortunately, we had a perfect run, charging six times without delay, problem or queueing. And if you’re thinking that six is rather a large number for that length of trip, you’d be right, and we could have done it in fewer stops. But there are different approaches to recharging your car. I decided to go for lots of quick partial charges (each typically a 15-20 min stop) because the rate at which the batteries charge slows down noticeably as they fill up: on these ‘rapid’ chargers at motorway service stations, it’s quicker to charge from 0%-80% than it is from 80%-100%, but you still get the same miles-per-percent. Also, I hadn’t visited any of these locations before, so I was curious to see more of them, and also didn’t know what to expect in terms of congestion. Sub-zero temperatures also reduce your range significantly if you want to keep your toes warm!

The upshot is that a journey like this, even when things are going perfectly, took about an hour longer in each direction than it would have done if we were burning dinosaurs. Richard was a trooper and raised no objection to getting up for a six o’clock departure. For some people, that would be unacceptable. Personally, I find I rather like it – I would normally stop at least once en route anyway and I suspect that getting out and stretching my legs every 40 mins or so is very beneficial from a safety point of view. I certainly arrive feeling more relaxed than in the old days. The extra time you spend on occasional long journeys is offset by the fact that I never have to visit petrol stations during the week. And it’s still much quicker than using public transport.

It’s also much cheaper. Many non EV-owners don’t realise that a significant proportion of public chargers are free to use, including the Ecotricity ones found at many service stations. This means that the ‘fuel’ cost to get the two of us from Cambridge to Sheffield and back yesterday was around £2.50, since we only paid for the charge I did at home before we set off.

But that’s about to change. In a podcast this week the founder of Ecotricity announced that they would start charging for charging in ‘a couple of months’. This comes as no surprise: we knew the free ride couldn’t last forever. Some welcome it, because the reliability of the network should improve when out-of-action chargers mean a loss of revenue. Hopefully the numbers of charging stations will also increase, and it’s less likely that the ‘pumps’ will be blocked by casual chargers, or those with plug-in hybrids, who don’t really need it, leaving more of them free for those with pure electric vehicles, who do.

But we’re all wondering what Ecotricity’s pricing will be. They are an honourable company with good motives, and are unlikely to resort to excessive profiteering from their effective monopoly on much of the UK’s motorway network. On the other hand, there are large chunks of the country that they don’t cover — try going south of Gatwick, for example — and the rapid chargers available in those areas from other companies are often selling their electricity with a 5x markup, such that petrol is a cheaper alternative. Even at those rates, it would take a long time to recoup the tens of thousands of pounds needed for a 50kW rapid charger installation. In due course, as EV ownership and awareness increases, and competition starts to become more real, the financials will change. After all – installing a petrol station is outrageously more expensive, but you can be sure of a flow of regular customers throughout the day. Even if electricity at the service station proves more expensive than petrol, most people do 90-95% of their charging at home or work, so the benefits of going electric are still substantial.

I’m in the fortunate position of having an electric car with a ‘range extender’: a small 650cc generator in the back that allows me to double my electric range using a couple of gallons of fuel. So Richard and I could have gone from Cambridge to Sheffield using 50% electricity from home and 50% petrol. We were able to charge at our destination, so we could have done the same on the way home. This would have been faster, though we wouldn’t have felt quite so smug about our lack of CO2 emissions, or the fact that the whole trip cost us less than one of the lattes we consumed on the way, though it might still have cost us less than the sum total of all our lattes!

My somewhat pricey BMW is, however, the only car on sale in the UK at the moment which falls into this mostly-electric-with-a-little-bit-of-petrol category. Part of the reason I bought it was because it was so perfect for riding out this transition that we’re going through. Those who own, or sell, pure-electric vehicles will be watching the Ecotricity prices with rather more skin in the game.

I think it’s vital that the other key part of our successful trip yesterday: the fact that there was a space available immediately at every charge point we visited, continues to be the norm, until they are much less of a scarcity or the range of affordable electric vehicles increases substantially. That means that companies will probably continue to need substantial government incentives to keep installing them ahead of the growth in electric vehicle sales, because it’s going to be hard to pay for them simply by charging for electricity in the short term. In the long term, however, such an investment will definitely be worth it for the nation.

We drive in interesting times.

Only six years away

20151219-23133107-Edit-600Six years. Not long after the next general election. That’s the estimate as to when electric cars will become cheaper than their petrol-powered predecessors, from a Bloomberg report quoted by Wired in ‘The Electric Car Revolution Is Now Scheduled for 2022‘. Worth a read.

The estimate makes certain assumptions about continued government support etc, so it may be out by a few years, but the principle is right.

One of the things I love about my car is the simplicity – I have no gearbox, no exhaust system, no oil sump, no cambelt, tappets, head gaskets or piston rings. Mine is also made mostly of aluminium and carbon fibre, so rusting shouldn’t be an issue.

This relative simplicity means that electric cars should be more reliable, longer-lasting and eventually cheaper, but it also raises interesting questions. Things like:

  • When the metals needed for batteries become more important than oil, which countries will we have to be nice to? Or invade?

  • Will the business model of dealers have to change when servicing costs are lower and cars last longer?

  • What will be the thing that causes me to sell this and buy a new car? In the short term, probably the opportunity for increased range, but eventually it may be that my car’s CPUs can’t run the latest version of the BMW operating system?

  • How quickly will the electricity grid and service-station infrastructure be able to change to support a world where transport is predominantly electric, once electric cars become the economically-preferable option, and not just something for enthusiasts like me?

I assume that eventually, every supermarket car park, every park & ride, every pay & display, will have inductive loops in significant numbers of their parking spaces, so you’ll be doing lots of little charges throughout your day without thinking about it, rather than needing to seek out special charging locations. That’s probably the right model for residential streets in cities where there’s no off-street parking, too. But I wonder how the transition will take place.

The great thing is that, right now, installing a charging point for your customers is something that any country pub or B&B can do – a very different proposition from becoming a petrol station. 🙂

Hope my car doesn’t have number-plate envy…


© Copyright Quentin Stafford-Fraser