Following on from last week's post : there is no excuse, ever, for using your brakes in a line of steady-flowing traffic. Being a nervous Nellie and tapping your brakes, even for a moment, causes your brake lights to come on, causing the person behind you to think you're slowing down, meaning they're likely to apply their brakes too. And so on back down the line until, on a motorway, about a mile behind you the traffic will come to a complete stop and your nervous driving has caused a phantom traffic jam for no reason.
The answer to this is simple : take your foot off the accelerator. The car will slow down - trust me. It doesn't matter if you're driving a manual or an automatic - once you take your foot off that pedal, the car will slow down. Not as much as it does with the brakes, but enough, in normal traffic, to accommodate the slight variations in speed and following distances that you get on motorways and main roads.
Of course the reason this happens, for the most part, is because (a)people are just not taught to drive properly any more and (b)people spend so much time texting, using their phone or otherwise being distracted whilst in their mobile entertainment complexes that when they finally do look out the window, they realise they're a bit too close to the person in front.
So I'm with Jeremy Clarkson on this one - people who brake in steady flowing traffic need to be taken outside and shot.
Monday, March 24, 2014
Monday, March 17, 2014
Driving with your foot on the brake does not make you safer.
I don't know if it's because people learn from their parents, and their parents do it all the time, but drivers around here have this annoying habit of driving with their left foot resting on the brake pedal. I once asked someone I know who drove like this and they said it was because it was safer - having their foot there meant they could brake more quickly.
Wrong. It is not safer. In fact you're more likely to cause an accident by doing this, in one of three ways. First, when your foot is resting on the brake pedal, there's enough pressure that the brake light switch is engaged. Everyone behind you sees you driving along, but not slowing down, with your brake lights on. When you do finally slow down, there's no indication of that and you'll get hit from behind. It's called "cry wolf" - your brakes lights have been on for so long that the driver behind you no longer believes them.
The second method by which you're going to cause an accident is because of the lack of calibration in your left leg. Muscle memory in your right leg knows, from driving experience, how much pressure to apply to the throttle and the brake. Your left leg, by comparison, is normally either used for the clutch (which is much heavier than the brake in almost every car), or your foot would normally be sitting on the foot rest if you drive an automatic. Either way, this means if you do use your left foot to brake, you'll step on the pedal too hard and either lock the brakes, or cause the ABS to come on. This will take you by surprise and you'll do something silly resulting in a crash.
The third method by which you're going to cause an accident is because your brakes are getting hot. The weight of your foot on the brake not only turns on the brake light switch but it will also be lightly applying the brakes all the time you're driving. Not enough to slow you down, but enough that the pads are touching the rotors. This makes the pads and rotors get hot, which makes them expand. In severe cases, this can (and does) cause the brakes to lock unexpectedly. This particular condition is easy to overcome by taking your foot off the brake pedal when it happens, but typically if you're minding your own business and your car suddenly brakes hard and you lose control - it will take you by surprise and the last thing you'll do is take your foot off the pedal.
So take that left foot off the brake and put it where it's supposed to be.
Wrong. It is not safer. In fact you're more likely to cause an accident by doing this, in one of three ways. First, when your foot is resting on the brake pedal, there's enough pressure that the brake light switch is engaged. Everyone behind you sees you driving along, but not slowing down, with your brake lights on. When you do finally slow down, there's no indication of that and you'll get hit from behind. It's called "cry wolf" - your brakes lights have been on for so long that the driver behind you no longer believes them.
The second method by which you're going to cause an accident is because of the lack of calibration in your left leg. Muscle memory in your right leg knows, from driving experience, how much pressure to apply to the throttle and the brake. Your left leg, by comparison, is normally either used for the clutch (which is much heavier than the brake in almost every car), or your foot would normally be sitting on the foot rest if you drive an automatic. Either way, this means if you do use your left foot to brake, you'll step on the pedal too hard and either lock the brakes, or cause the ABS to come on. This will take you by surprise and you'll do something silly resulting in a crash.
The third method by which you're going to cause an accident is because your brakes are getting hot. The weight of your foot on the brake not only turns on the brake light switch but it will also be lightly applying the brakes all the time you're driving. Not enough to slow you down, but enough that the pads are touching the rotors. This makes the pads and rotors get hot, which makes them expand. In severe cases, this can (and does) cause the brakes to lock unexpectedly. This particular condition is easy to overcome by taking your foot off the brake pedal when it happens, but typically if you're minding your own business and your car suddenly brakes hard and you lose control - it will take you by surprise and the last thing you'll do is take your foot off the pedal.
So take that left foot off the brake and put it where it's supposed to be.
Monday, March 10, 2014
Getting better battery range in your EV
Right now, range anxiety and price are still the main barriers to entry for most people looking at electric cars. The batteries don't charge fast enough and there's no battery-swap capability which leads many - myself included - to still shy away from a fully electric car because there's the nagging "what if" problem. Sure my EV has a range of 80 miles - plenty for a day's driving or more, usually. But "what if" I need to go a couple of extra errands? Blam. Dead, with no way to get home and no way to recharge. In a petrol car, that's not a problem - fill up and keep going.
Battery capacity has been slow to catch up with the needs of electric vehicles but there's a possibility that could change. A couple of weeks ago, researchers at UNC Chapel Hill stumbled on a discovery whilst trying to design a material to keep sea life from sticking to boat hulls. Lithium-Ion batteries - the most common type used today - are great but do rather have a habit of going up in flames. The discovery made in Chapel Hill would replace the unstable, fire-prone chemicals in the electrolyte with a very stable polymer instead. It's called perfluoropolyether (PFPE) and it dissolves lithium salt - something required to produce conductivity in batteries. Most polymers don't mix with salt, but this one does and as a bonus, it's nonflammable.
So why is this important? Well the entire way a battery works is by moving ions around between the electrode and cathode, the direction being dependent on whether the battery is being charged or discharged. The rate of movement of the ions is called "transference rate" and typically it's around 0.2 for the average Li-Ion battery. The PFPE electrolyte, however, has a transference rate closer to 0.9. Not only that but it has an operating temperature range of -90°C to +200°C - far lower and higher than you'd ever find in a passenger car in daily use.
So what does this mean? Simple - higher transference means better capacity, meaning a Volt or a Tesla could instantaneously get over a 4x increase in range by using batteries with a PFPE electrolyte.
Range anxiety will still be there, but quadrupling the mileage means that odd unexpected errands and diversion will no longer be cause for concern.
Now if we could get swappable PFPE Li-Ion battery packs for cars - 600 mile range and instant swapover? THEN we'll see mass market adoption because at that point, road trips and long-distance journeys become possible without having to stop every 150 miles or so to hang around a charging station for an hour or more.
Battery capacity has been slow to catch up with the needs of electric vehicles but there's a possibility that could change. A couple of weeks ago, researchers at UNC Chapel Hill stumbled on a discovery whilst trying to design a material to keep sea life from sticking to boat hulls. Lithium-Ion batteries - the most common type used today - are great but do rather have a habit of going up in flames. The discovery made in Chapel Hill would replace the unstable, fire-prone chemicals in the electrolyte with a very stable polymer instead. It's called perfluoropolyether (PFPE) and it dissolves lithium salt - something required to produce conductivity in batteries. Most polymers don't mix with salt, but this one does and as a bonus, it's nonflammable.
So why is this important? Well the entire way a battery works is by moving ions around between the electrode and cathode, the direction being dependent on whether the battery is being charged or discharged. The rate of movement of the ions is called "transference rate" and typically it's around 0.2 for the average Li-Ion battery. The PFPE electrolyte, however, has a transference rate closer to 0.9. Not only that but it has an operating temperature range of -90°C to +200°C - far lower and higher than you'd ever find in a passenger car in daily use.
So what does this mean? Simple - higher transference means better capacity, meaning a Volt or a Tesla could instantaneously get over a 4x increase in range by using batteries with a PFPE electrolyte.
Range anxiety will still be there, but quadrupling the mileage means that odd unexpected errands and diversion will no longer be cause for concern.
Now if we could get swappable PFPE Li-Ion battery packs for cars - 600 mile range and instant swapover? THEN we'll see mass market adoption because at that point, road trips and long-distance journeys become possible without having to stop every 150 miles or so to hang around a charging station for an hour or more.
Monday, March 3, 2014
Rotating your tyres - things to be aware of.
It's common wisdom that rotating your tyres is A Good Thing. It helps even out wear especially on front-wheel-drive or rear-wheel-drive where one pair of tyres will typically wear quicker. There's a couple of things you need to be aware of when having a tyre rotation done though. Unidirectional tyres must be kept on the same side of the car - typically the front and rear lefts will be swapped, and the front and rear rights will be swapped.
If you don't have unidirectional tyres, then front-left to back-right and vice versa is just fine.
But there's a slight wrinkle in the scheme with a lot of modern cars : TPMS. For the average family car, the TPMS system (the tyre pressure monitors built into each wheel) is a single-point-of-failure system, meaning that if any one sensor registers low pressure, the car will present a single warning light on the dash and it's up to you to find the tyre in question. For higher end vehicles though - Range Rovers, BMWs, Mercedes and the like - they sometimes have TPMS that will tell you which tyre needs attention. This makes tyre rotation more complicated because you either have to take the tyres of the rims to ensure each rim and sensor stays on the correct corner of the car. Or you need to have the car re-learn the location of each sensor afterwards. Generally speaking this isn't easy to do - it normally requires access to the computer via the OBD-II port and access to someone who knows that they're doing.
There is one manufacturer - and I can't remember who it is - who made this easy though. They have a mode where you, as the owner, can put the TPMS into 'learn' mode and then it shows you on the dash which sensor it wants to learn, in order. To 'teach' it which sensor is where, you bleed a little air out of the tyre. So when the car indicates "left front", you go and blip a little air out of the left front tyre, and it then associates that sensor (the one that changed) with the front left corner.
Anyway - the point is this - by all means rotate your tyres, but be aware of the little pitfalls when it comes to tread directionality and TPMS.
If you don't have unidirectional tyres, then front-left to back-right and vice versa is just fine.
But there's a slight wrinkle in the scheme with a lot of modern cars : TPMS. For the average family car, the TPMS system (the tyre pressure monitors built into each wheel) is a single-point-of-failure system, meaning that if any one sensor registers low pressure, the car will present a single warning light on the dash and it's up to you to find the tyre in question. For higher end vehicles though - Range Rovers, BMWs, Mercedes and the like - they sometimes have TPMS that will tell you which tyre needs attention. This makes tyre rotation more complicated because you either have to take the tyres of the rims to ensure each rim and sensor stays on the correct corner of the car. Or you need to have the car re-learn the location of each sensor afterwards. Generally speaking this isn't easy to do - it normally requires access to the computer via the OBD-II port and access to someone who knows that they're doing.
There is one manufacturer - and I can't remember who it is - who made this easy though. They have a mode where you, as the owner, can put the TPMS into 'learn' mode and then it shows you on the dash which sensor it wants to learn, in order. To 'teach' it which sensor is where, you bleed a little air out of the tyre. So when the car indicates "left front", you go and blip a little air out of the left front tyre, and it then associates that sensor (the one that changed) with the front left corner.
Anyway - the point is this - by all means rotate your tyres, but be aware of the little pitfalls when it comes to tread directionality and TPMS.
Monday, February 24, 2014
"Cheap" petrol or gas is a false economy
Time for a re-post on an often-discussed topic - "cheap" gas, or as it used to be known in England - supermarket petrol. I don't use it, and neither should you. Yes, it's cheaper up-front, but there's a reason for that. It's also the reason that supermarket petrol in the UK is now not much different in price to regular petrol stations; they had to change their ways.
So why is the petrol or gas at places like Costco so much cheaper per gallon than everywhere else? It's not a simple answer - the base petrol stock is identical for every vendor, but it can be broken down into three basic parts, as follows:
1. Filtering. Tanker drivers can fill their tanks for petrol station deliveries at two different filling locations in most refineries. The difference between the regular and the premium fuel dumps is the filtering process. The premium fuel goes through additional filtering and purifying before being distributed. This may not sound like much, but the regular stuff puts the responsibility on the individual petrol stations to regularly clean out their underground tanks and change their pump filters. I think we all know how often that is likely to happen. That means there's a greater chance of sand, grid, rust and other crud getting into your tank from a cheap petrol station, meaning a greater likelihood of blocked fuel filters and/or fuel system damage.
2. Additive packs. Once the tanker is loaded with the regular petrol, the driver goes off on the delivery rounds. For premium loads, they make a second stop at the additive dump. This is where the extra detergents, fuel additives, stabilisers and other products are added. (Things like the Texaco / Chevron Techron). They're dumped into the tanker in liquid form and get mixed in to the fuel load simply by being in a moving tanker truck. Cheaper petrol stations don't have these additive packs and it's open to debate whether that's a good or a bad thing, but generally speaking, a decent detergent additive in your petrol is not a bad thing.
3. The biggie: separate trucks. The cheap brands use the same tankers for everything. One day it might have industrial diesel in it. The next day, commercial petrol, and the day after that, farm-grade diesel or worse - raw crude. Theoretically, the tanks ought to be cleaned out between each load, but in reality, the deadlines and costs are so tight that this just doesn't happen. So it's not only possible, but entirely normal that when you fill up with petrol from a cheap filling station, you're getting an impure blend of petrol, diesel, and in some cases, raw crude. The bigger name-brand filling stations and companies always use dedicated tankers for each product. Once a tank is allocated for petrol, that's all it carries. Same for diesel, same for crude.
In the UK, supermarket petrol exploded (pun intended) in the 90's and people flocked to it because it was so much cheaper. All of the above reasons were why, and after a particularly bad spate of problems of sludge in people's engines (caused by an impure mix of petrol and raw crude), they had to 'clean up' their act, so-to-speak. Now that most supermarkets in the UK have dedicated trucks and additive packs, their cost to the public is not that much different to mainstream stations. But this hasn't happened in the US yet, and supermarket petrol is only just starting to boom over here. The only question is for vendors like Costco - they sell petrol as a loss-leader to get people to their facilities, and it's unclear if they are using the cheap, unfiltered, 'dirty' truck petrol, or the mainstream products. I think it's different in different areas of the country / world, but in my local area, Sam's Club and Costco are both stocked from Shell-branded tankers, meaning it's the "good stuff" but sold at a loss (well not really as you have to pay a membership fee to fill up there).
So why is the petrol or gas at places like Costco so much cheaper per gallon than everywhere else? It's not a simple answer - the base petrol stock is identical for every vendor, but it can be broken down into three basic parts, as follows:
1. Filtering. Tanker drivers can fill their tanks for petrol station deliveries at two different filling locations in most refineries. The difference between the regular and the premium fuel dumps is the filtering process. The premium fuel goes through additional filtering and purifying before being distributed. This may not sound like much, but the regular stuff puts the responsibility on the individual petrol stations to regularly clean out their underground tanks and change their pump filters. I think we all know how often that is likely to happen. That means there's a greater chance of sand, grid, rust and other crud getting into your tank from a cheap petrol station, meaning a greater likelihood of blocked fuel filters and/or fuel system damage.
2. Additive packs. Once the tanker is loaded with the regular petrol, the driver goes off on the delivery rounds. For premium loads, they make a second stop at the additive dump. This is where the extra detergents, fuel additives, stabilisers and other products are added. (Things like the Texaco / Chevron Techron). They're dumped into the tanker in liquid form and get mixed in to the fuel load simply by being in a moving tanker truck. Cheaper petrol stations don't have these additive packs and it's open to debate whether that's a good or a bad thing, but generally speaking, a decent detergent additive in your petrol is not a bad thing.
3. The biggie: separate trucks. The cheap brands use the same tankers for everything. One day it might have industrial diesel in it. The next day, commercial petrol, and the day after that, farm-grade diesel or worse - raw crude. Theoretically, the tanks ought to be cleaned out between each load, but in reality, the deadlines and costs are so tight that this just doesn't happen. So it's not only possible, but entirely normal that when you fill up with petrol from a cheap filling station, you're getting an impure blend of petrol, diesel, and in some cases, raw crude. The bigger name-brand filling stations and companies always use dedicated tankers for each product. Once a tank is allocated for petrol, that's all it carries. Same for diesel, same for crude.
In the UK, supermarket petrol exploded (pun intended) in the 90's and people flocked to it because it was so much cheaper. All of the above reasons were why, and after a particularly bad spate of problems of sludge in people's engines (caused by an impure mix of petrol and raw crude), they had to 'clean up' their act, so-to-speak. Now that most supermarkets in the UK have dedicated trucks and additive packs, their cost to the public is not that much different to mainstream stations. But this hasn't happened in the US yet, and supermarket petrol is only just starting to boom over here. The only question is for vendors like Costco - they sell petrol as a loss-leader to get people to their facilities, and it's unclear if they are using the cheap, unfiltered, 'dirty' truck petrol, or the mainstream products. I think it's different in different areas of the country / world, but in my local area, Sam's Club and Costco are both stocked from Shell-branded tankers, meaning it's the "good stuff" but sold at a loss (well not really as you have to pay a membership fee to fill up there).
Monday, February 17, 2014
Why can dealers still get away with such terrible advertising practices?
Our local VW dealer had an incredible promotion a couple of months ago - at least it was incredible on the face of it. They had a media blitz advertising $8000 below MSRP on all new cars. Remember the old adage about 'if it seems to good to be true' ? Well naturally they weren't selling new cars that cheaply - no dealer could - they'd lose their shirt if they did. What was curious in this case was that there wasn't any fine print either. It was only if you went to the dealer and talked to them that you found out what the scam was, and it was this: the cars were all used or pre-owned cars, and yes they were all $8000 below the MSRP of a new car. But how could they advertise this discount on "all new cars"? Simple. The used cars were new to their stock list at that dealer.
The other huge scam is when you see TV commercials showing a really good deal. Buy a Camry today for $uper Cheap! Those ones all do have fine print but it goes by so quickly that you never really see it. In fact they are actually selling a Camry (singular) at that price. It's one particular model, with a very specific stock number in their inventory. Or it was. Of course by the time you go down to try to buy any Camry at that price, the one specific one used in the TV commercial is long gone and you're saddled with the regular price on all the others.
How about the "cash back" deals. Or the ones where they offer to pay you $1000 more than the car is worth? More scams, obviously. Yes they'll give you cash in your pocket, and/or $1000 above average for your trade-in, and they do it by simply adding that on to the loan for the new car. So instead of loaning (for example) $15,000, you're actually loaning $20,000 - $15k for the car, $1k "extra" for your trade-in, and a $4k cash loan. The dealer makes more money, the dealer's finance company makes more in interest and payments off you, and you end up with the same car but more debt than you'd intended.
The crazy thing is that all these practices are completely legal. They simply rely on people's fear of car dealers and unwillingness to challenge the status quo. It's a terrible state of affairs that needs some serious attention.
The other huge scam is when you see TV commercials showing a really good deal. Buy a Camry today for $uper Cheap! Those ones all do have fine print but it goes by so quickly that you never really see it. In fact they are actually selling a Camry (singular) at that price. It's one particular model, with a very specific stock number in their inventory. Or it was. Of course by the time you go down to try to buy any Camry at that price, the one specific one used in the TV commercial is long gone and you're saddled with the regular price on all the others.
How about the "cash back" deals. Or the ones where they offer to pay you $1000 more than the car is worth? More scams, obviously. Yes they'll give you cash in your pocket, and/or $1000 above average for your trade-in, and they do it by simply adding that on to the loan for the new car. So instead of loaning (for example) $15,000, you're actually loaning $20,000 - $15k for the car, $1k "extra" for your trade-in, and a $4k cash loan. The dealer makes more money, the dealer's finance company makes more in interest and payments off you, and you end up with the same car but more debt than you'd intended.
The crazy thing is that all these practices are completely legal. They simply rely on people's fear of car dealers and unwillingness to challenge the status quo. It's a terrible state of affairs that needs some serious attention.
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