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If you're gonna factor in transmission line losses and charging loss, then you also have to factor in idling and drivetrain losses, which brings the fuel efficiency of an ICE down to about 15%. Not counting the energy required to actually make the fuel in the first place (which is also not zero). More importantly, though, electric cars are source-neutral: they don't give a shit if their electricity comes from coal, nuclear, or solar.

That's a bit disingenuous. You can't pick out a single stage of the process and compare that while ignoring everything else if you want an honest assessment of the efficiency.

Let's make up an example. Let's say you have a source of fuel, a power plant that can burn that fuel, a testing ground that's 100 miles further away from the fuel source than the power plant, and two vehicles that can utilize the fuel. Internal combustion cars are generally about 15% efficient. Electric engine cars are 85-90% efficient. Fossil fuel power plants are about 33% efficient. Your transmission numbers are 99.86% for gasoline and 99.25% for electricity over 100 miles.

So overall efficiencies are:
Gas: 1 * 0.9986 * 0.15 = 0.14979
Electrical = 1 * 0.33 * 0.9925 * 0.88 = .28822

So over a distance of 100 miles Electric cars are still almost twice as efficient, even with the extra losses in transmission. (Admittedly this is for "normal" internal combustion cars, i don't have the figures to hand for the average efficiency of hybrid cars.)

Doing a little quick math (it's been forever since i've had to solve for a variable, so i'm just plugging it into a spreadsheet) it looks like the break-even point is about 10,700 miles. So if the distance from the fuel source was over 10,700 miles, you'd be better shipping the fuel to the car rather than converting it to electricity on-site and transmitting it to the destination. Though obviously over such an extreme distance a lot of other factors would come into play and overwhelm the simple equation.

Sources:
http://consumerenergycenter.org/transportation/consumer_tips/vehicle_energy_losses.html
https://en.wikipedia.org/wiki/Fossil-fuel_power_station
http://www.eetimes.com/document.asp?doc_id=1273932

There may be more accurate numbers out there, so the exact outcome might differ, it's clear that better efficiency in just a single stage of the operation does not dictate an overall higher efficiency.

AlecC wrote

Explain "major disaster"

An explosion as powerful as a hermo-nuclear bomb. The worst case accident would be the reactor exploding and burning off Earth's atmosphere, much worse scenatio that any accident from a fission reactor.

It seems to me that you are extrapolating to fusion reactors the failings of fission reactors, when one of the major virtues of fusion reactors is that they are inherently not susceptible such failings. A fission reactor is fuelled up with about ten of years of fuel, and has days of energy unstoppably being generated at any moment, so it is a disaster waiting to happen. Where as a fusion reactor has tenths of a second of fuel in the reactor at any moment and can be turned of in milliseconds. The energy available to cause a disaster is several orders of magnitude different.

Irrelevent, an accident from fusion reactor is far more dangerous than a fission rector, no matter how much fuel is used at any time. Neither fission nor fusion should be used.

The problem with solar and wind are that they are so diffuse. We have to cover many acres of land with concrete and some sort of energy collector. A fusion reactor would be one building delivering the outputs of several thousand of the largest windmills, or several square miles of solar collectors. the environmental cost of building the solar farms (concrete, roads, solar cells, pylons) is something to be avoided.

Usuable areas of land aready exist for both solar and wind. Think of the tops of buildings and houses. Then there is also areas of land with no trees like farms, deserts, etc. There is more than enough land available on Earth for solar panels and wind mills without having to cut trees or pave new roads. That is theadvantage of solar and wind, both are environmentaly friendly and they are decentrallized. Coupled with geothermal heat pumps solar and wind energies will eliminate:

• The need of combustion of any kind
• environmental disasters
• power shortages
• monopolies on power generation

No I am not the one confused, you are my friend. Confused from the propaganda spewed by the power companies lies. Decentralized power sources are the way of the futre, while centralized power sources are obsolete ways of making greedy fucks rich at th expense of the planet and all of its inhabitants.

Sure, I buy the last part, I just don't get why light bulbs are unique.

Lightbulbs aren't unique. This isn't the only government policy that is directed at residential energy usage; there are many others, at both the federal and state levels.

So do absurdly large televisions. But nobody that I know of is proposing to mandate thermostats that won't heat/cool above/below certain government-prescribed threshholds, or force people to buy more reasonably sized TVs.

But that wouldn't be analogous to the efficiency standards for lightbulbs, anyway.

What would be analogous to the efficiency standards for lightbulbs would be, e.g., heating and cooling efficiency standards for heating and cooling units installed in new homes. Which Congress, in fact, established in 1992, long before the standards at issue on lightbulbs.

Or efficiency standards for televisions, which Congress authorized DOE to establish in 1989, and DOE has announced this year that they intend to establish and which would be effective in 2016.

Just because lightbulbs get talked about on Slashdot a lot doesn't mean they are somehow being treated different than everything else.

Sources:
Heating/cooling
TV

You raise interesting points, but as you say, you've only speculated. If you had done a Google search for "shutting off engine," you would have found http://www.consumerenergycenter.org/myths/idling.html provided to us by the state in which all things cause cancer CA and where emissions laws like those in North Dakota, where I'm from, might as well be viewed as permissive of pouring-gasoline-on-the-ground-and-lighting-it-aflame (no one checks our vehicle emissions). Long story short, CA found that 10 seconds is all it takes to get a return on your investment. The article also notes that not all gas is burned at idle. This is true and causes a non-stoichiometric reaction producing extra CO and unburned hydrocarbons. So apart from the decreased gasoline consumption, you spew out less gas too!

As a side note, I do this routinely and don't find it a great inconvenience.

Actually, I saw that and others with that figure. If you had kept on using Google you would notice that others disagree with that figure, including various vehicle manufacturers (who are more likely to have an accurate figure on their particular vehicle than a government agency that only tested 2 or 10 or 20 vehicles).

And I also noted that in my post: the fact that various government agencies and auto manufacturers disagreed - hence the suggestion that a lot mroe research in this area needed to be done.

And as someone else noted, though hybrids may be designed with constant restart in mind, pure fossil fuel vehicles are not.

You raise interesting points, but as you say, you've only speculated. If you had done a Google search for "shutting off engine," you would have found http://www.consumerenergycenter.org/myths/idling.html provided to us by the state in which all things cause cancer CA and where emissions laws like those in North Dakota, where I'm from, might as well be viewed as permissive of pouring-gasoline-on-the-ground-and-lighting-it-aflame (no one checks our vehicle emissions). Long story short, CA found that 10 seconds is all it takes to get a return on your investment. The article also notes that not all gas is burned at idle. This is true and causes a non-stoichiometric reaction producing extra CO and unburned hydrocarbons. So apart from the decreased gasoline consumption, you spew out less gas too! As a side note, I do this routinely and don't find it a great inconvenience.

Thanks for running some of the numbers, although I don't know whether a 1000W heater is enough (I'm not saying it isn't - I'm saying that I don't know one way or the other). I do want to see it in action before I would consider buying it, though. I know the survivability with a gas engine and full tank and have developed the skills to maximize that survivability. I need to see actual tests of heating the car against the frigid outdoors for a few days straight on a 50% charge before I can really evaluate that.

But don't miss my real point. It is rare to get stuck in a snowbank beyond the point you can rock your car back out of it, but that's no excuse not to prepare for the possibility. It happens more often than serious collisions but you wouldn't want a car without airbags and seat belts, either. The cost-benefit on this works out in favor of gas engines so far.

Now you are moving the goalposts. In your original post you talked about "morning (and hope of rescue)" coming, now you are talking about spending a "few days straight" in the snowbank. This page says that idling your car uses about 1 gal/hour, to spend a few days in an idling gasoline car you are going to need a 40-60 gallon tank. My car carries about 10 gallons, even with a full tank I could only idle overnight. You are holding the electric car to a higher standard than the gasoline car. There are plenty of reasons not to use an electric car, you don't need to fabricate one.

You get modded informative, but nowhere do you give any proof of your refinery cracking theory. I work in the oil business, and while I'm not in refining (I'm in distribution), I do know that API (American Petroleum Institute) has repeatedly said there is absolutely zero benefit in using a higher grade gas than recommended by the manufacturer. But if you don't believe API, than maybe believe the California Energy Commission http://www.consumerenergycenter.org/transportation/consumer_tips/regular_vs_premium.html, or if you don't believe in organizations (private or government) than maybe a car talk radio show? http://www.cartalk.com/content/features/premium/questions.html

But please, feel free to keep buying premium gas, it's quite profitable on our end :)

Surprisingly for an emerging technology, costs seem have risen somewhat since I installed my panels in 2003. A quick online check shows that panels are actually about 10-15% more now, which is not what I expected. In 2003, the installed cost was about $8400 per kW, but based on panel costs I'd suggest allowing $9,000 per kW at least now.

My installer was http://www.skypowersystems.com/ - their work and attention to detail was fantastic, but the company has changed ownership since my install was completed. I'd also suggest checking out http://www.regrid.com/ which was my second choice. I have a lot more information about how I selected solar which I would be happy to share with you. If you write to me at watt9999@mac.com (that's a temporary email address) I'll be happy to help in any way I can.

But I used to work for a solar photovoltaic system installer, and I was very well-versed with the prices for the common residential customer, at least in California, and I have somewhat kept up to date with what's going on in the industry.

Back in 2003, a 2.5 kw AC system cost about $10k to $12k to install, depending on various conditions, such the type of roof. Prices usually scale proportionally as you increase the size of the system. Nowadays, I hear the figure is about $16k to $18k.

Why the increase of the prices?

One of the biggest factors is that, at least in California, the CEC rebate (for customers of most power utility companies) was $4.50 per watt back around ~2002, going down by twenty to fifty cents every six months. It used to cover more than half the cost of any installation up to 30 kW.

These days it's $2.60 per watt. While solar panel prices have gone down a bit, it no longer covers more than half the cost.

Other factors resulting in higher prices: the value of the dollar has gone down in the last couple years, and since many major photovoltaic panel manufacturers (ie: sharp, kyocera) and inverter manufacturers(Sunny Boy) are foreign, that results in higher prices here. Also, due to worldwide demand of silicon in the last couple years, there has actually been a shortage of panels for the company I used to work with. (though I don't expect the shortage to last forever)

Beyond that, the labor part of the installation usually significantly adds to the bill -- my guess, probably around $5k for a typical residential installation of 2.5kW, depending on the contractor.

That's not to discourage people from getting a solar photovoltaic system installed. Technology and mass production will always result in a downward force on prices. Even if solar photovoltaic systems increase in price, it's really the cost per watt from the local energy utility company in comparison to the cost of solar installations that customers consider. And energy utility prices in California are some of the highest in the country, and mostly continue to increase.

You're not clear on whether or not you're counting state and federal rebates on your PV costs. In California we've got this program which provides serious cash for people interested in installing their own renewable energy (RE) system. If you don't live somewhere with such a rebate program you might try writing to your state representatives and ask them why.

Also, your brand new PV system will likely last at least 25 years, possibly much more. Such a system can also add quite a bit of value to your house. After 15 years your PV panels will be doing nothing but saving you money and raising the value of your house. On a 30 year scale the PV system will make you about as much as if you had invested it, possibly more if you can get tax credits and/or rebates. You're also likely to make some money on the PV system when you sell your house since it is a 'utility' upgrade more than a stylistic one.

actually, a full refrigerator is more efficient than an empty one.

consumer energy center

Appreciating the merits of duct tape may have been a clever observation once (e.g. in the 70's, it wasn't carried in all hardware stores, much less every retail store, pharmacy and gas station) but now it's cliche - the stuff of stand-up comedy routines that *everyone* understands, even if they are completely 'tape incompetent' (We've all seen it). I see a wide array of uselessly cheap shiny grey plastic (or even paper) so-called duct tapes, because manufacturers know that most people are aware of its reputation, but not its properties and use, and will buy anything that looks similar.

Too many of the posts sound like "Level 1 geek wannabes" Top quality gaffer tape (for example) may run up to $20 a roll, but it's still pennies per job and it'll handle jobs the plastic stuff won't (including things you wouldn't expect - it's often better for sealing leaks than duct tape, which studies have shown to be the worst option for sealing ducts) I carry top notch gaffer tape in my house and car, not duct tape. I also keep countless other plastic tapes (packing tapes, stranded tapes, etc.) that have greater strength and other properties. Nowadays 'moving' and packing supplies are widely stocked.

Every geek should be able to improvise, true, but they should also have a fine understanding of the fine points of common tapes. It's the difference between success and failure for those who actually improvise instead of imagining doing it. 95% of the time, a top quality gaffer tape will beat the pacts off duct tape, but the guy in the article knows the duct tape mystique will sell where genuine gaffer tape quality won't.

The one true advantage of duct tape is that it is somewhat more widely available, in the stores and in your friend's closets. In the 70s, masking tape was everywhere and the duct tape crowd knew masking tape would quickly fail, if it worked at all, for most jobs where duct tape works great- but geek-wannabes and kids used masking tape for every job, and considered themselves clever. A slight edge in availability does not make it any better or less ignorant a default choice. Today, duct tape occupies the place in the market that masking tape once did: a passable cure-all for those who don't know better options exist or can't be bothered to think ahead and stock them.