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Comment: Re:Thermal Management (Score 1) 386

by hsu (#46829967) Attached to: Will the Nissan Leaf Take On the Tesla Model S At Half the Price?

Heat generated is proportional to speed of driving or charging, not size of battery. For driving, the heat generation is likely same or less, and likely stays in manageable numbers. I do not see more than maybe 5 degree Celsius increase after driving the battery empty. For quick charging, for twice the charged amount you need maximum twice the amount of air flow to transfer the heat out of the battery system. Note that Leaf manages charging speed based on battery temperature already. This can mean it charges slower when the battery is too cold or warm. For overnight charging, no issue, heat generation is less than when driving.

Liquid cooling may offer a bit longer battery lifetime, or you might be able to get away with cheaper chemistry, but increased cost, servicing and extra weight easily negate your benefits. This might be sensible in very dense battery of a top-of-the line car such as Tesla, but if you need to keep budget in level for mass consumer market, liquid cooling does not pay off. It is likely that chemistry developments reduce need for it further, as new chemistry can be less picky on temperature. Loosing liquid cooling system will also loose you weight, so you get positive feedback on that as well, less battery capacity needed to move a lighter car.

Comment: 84 to 150 miles is 3.2 times more places to go (Score 1) 386

by hsu (#46829687) Attached to: Will the Nissan Leaf Take On the Tesla Model S At Half the Price?

Getting a 150 mile battery will increase the area you can go to by 3.2 times. This is a big increase and will make a difference for lots of people. Lots of cities become within range from anywhere in the city, leaving just really large metropolitan areas still needing more.

It is also much more likely that there will be a conveniently placed quick charger somewhere you need for a longer trip.

Another benefit for 150 mile leaf is that longer trips become much more comfortable for some quick charging related reasons: On 2013 Leaf, to travel 250 miles, you at least three charging stops, if you charge on quick charger up to 80%, ie. 3*30 minutes. People rather take gas car. For 150 mile battery you need one stop, and it will be maximum 1 hour. This is because quick chargers are quick only at empty batteries, and slow down quite quickly as the battery fills up (on Leaf). Larger battery will pull peak 44-50kW much longer, so you likely get juice for the remainder of the trip faster. Also, 1 hour stop is more useful for things like attraction visit, shopping or eating a good meal.

Trips longer than 250 miles, which still would be sensible with 150 mile ev, fall into narrow crack between "taking a car" and "it is faster and cheaper to fly", and thus it is less likely to make substantial financial difference for most people. Trips as long as 250 miles are much more likely to include an overnight stop, so slower overnight charging, much more widely available, becomes an option.

I have been driving Leaf for 5 months now, and my backup gas car still continues to have count of trips made of zero. I still expect to need a gas car during summer time, but it is becoming more and more obvious that keeping a gas car sitting unused for 9 months per year is not the solution. Car sharing, rental, etc is obviously becoming a lot cheaper for those occasional longer trips. For me personally, there are two cases where 150 mile battery would make sense for me. Travels to neighboring towns, and getting to summer cottage a bit further away. Both are 15 - 20 times per year, totaling, say, 30 trips. Money-wise, it would save me about 50-100 in gas per trip (I'm Europe), plus rental or amortized cost of owned gas car, 50-100, totaling savings of 4k+ per year. So, savings from from 150 mile battery can be substantial, and it would be no-brainer to pay added price of 5k for the larger battery, with 1 year payback time. For larger price hike, it would likely need a bit more consideration.

Whether normal consumers are as analytical as I tend to be is another matter. Today they are more likely to buy the cheaper gas car based on sticker price and start loosing money after couple of years.

Statisticians warning: The above ignores environmental, comfort, noise and trade balance issues, and considers money only.

Comment: Re:So - who's in love with the government again? (Score 1) 397

by hsu (#46801403) Attached to: Beer Price Crisis On the Horizon

This issue might be wider than just breweries and their by-products. There is another issue in regulation, which concerns small, local food (including beer) production, vs. big corporate food industry. I am looking this from European perspective, but the problem seems to be global and similarly motivated everywhere. Over-regulation can be really bad, and it is often lobbied for by larger industry, as it does not hurt them, but rather creates competitive advantage against new market entrants or mom-and-pop farmers and local foods. Few examples from Europe:

- In Europe, most smaller farmers have stopped butchering meat and selling it directly due to regulations which require very strict environment for meat processing. While this sounds great in health reasons, it killed pretty much all direct sales of meat from smaller farms. They can only butcher for their own consumption, or sell it under counter. in Europe, the commercial chain pays them less than 1/10th of the money they get if they butcher themselves and sell the meat directly to customers. The regulation here has little to do with health, it is all for corporate profits and keeping small farmers in line.

- In Europe most smaller farmers stopped keeping chicken, effectively removing non-industrial small farmer eggs and poultry meat off the market. This was due to ridiculous requirements for keeping chicken. No more picking breakfast eggs from neighboring farm in the morning.

- In France, they fought heavily for their cheese, as EU wanted to force all cheeses to be pasteurized. This would have been bad news for cheese lovers. I think the French farmers won on this, and we can still eat lovely cheeses from strange places, but likely the war against fresh food is still going on, with more and more regulation making small farmers' life and direct sales increasingly difficult.

- More local example, in Finland, local FDA-equivalent decided that it would be a good idea that local delicacy called Kalakukko, which is basically small fish baked in rye bread, to not be sold oven-fresh any more. Their logic was that if it gets cooled to fridge temperature first it somehow becomes safer to eat. When asked why, the spokesman said they know 3 cases of health issues related to eating the stuff. A quick calculation revealed that you have approximately equal chance to die in a airplane crash as you might get messed up stomach from this delicacy. Additionally, Kalakukko is baked in oven for really long time for purpose of softening the fish bits, so it actually is very well preserved food, used old times by travelers as it would not spoil quickly. Kalakukko eaters won this battle, but likely only due to complete ridiculousness of DFA claims.

I can see some point in being able to track down who made what bits of food in industrial food processing, as corporations tend to have complete lack of ethics in what comes to feeding us chemicals and falsifying contents of food they sell, but the result should not be killing sensible uses of materials, nor they should damage small, local food production. I do not know if this is the case with large corporations in this case, but by making it very strictly regulated you might actually kill your local micro-brewery instead of greedy corporation with "brewery" resembling a huge chemical factory producing tasteless alcoholic beer-like substance.

To me, traveling through places like French countryside by car, and only eating stuff picked from local markets has been huge enjoyment. I know that I am taking life-threatening risk of major food poisoning, but I have always wanted to die of eating good fresh food, drinking good local wine, and smoking cigars. Over-regulation has, politically unintended but likely industrially intended, consequences of effectively shutting down providers of these enjoyments. I am all ok with big industry labeling their stuff "All the raw materials of this food can be traced to production", as long as we can also have label "directly sourced traditional food", which is excepted from having to fill 25 forms for each food item, and paying for repeated checks and other bureaucracy.

Comment: Re:So - who's in love with the government again? (Score 1) 397

by hsu (#46801125) Attached to: Beer Price Crisis On the Horizon

If you have enough gases to generate explosions because of microbes making you methane, hydrogen or other burning gases, your problem is that you are not harnessing a basically free or byproduct energy source properly. Buy a micro turbine or other generator and get yourself some free electricity. Or process the resulting stuff into other fuels such as bio-fuels. People do this already, at least in Europe. If the amounts are not large enough for electricity generation, pipe it to your water heater for additional energy.

Comment: Re:Nuclear energy neglected by ignorance. (Score 1) 135

by hsu (#46388175) Attached to: NRC Expects Applications To Operate Reactors Beyond 60 Years

Simplified cost analysis:

Nuclear plant: Areva 1600 MW unit being built in Finland (and similar one in France, I think): Current cost estimate 8.5B euro (more than 11B USD). Raw cost per W (ignore service breaks for simplicity) becomes 5.3e/W. It does not take up that much space but due to people being allergic to nuclear power plant in their backyard, it needs to be located somewhere remote where there is cooling water available. Efficiency could be increased if the cooling water could be used for, say, heating application or industrial process. As the plants are typically some 35% efficient, there is large amount of excess heat generated which currently is not used.

Solar plant using ordinary panels: We need 24/3.5 times larger nominal power to get same production capacity, assuming 3.5 factor (quite common value in Europe), so we need about 11000 MW of solar panels. These cost, assuming they can be installed efficiently, about 1 euro per W (panels 0.6 + cabling and other installation stuff). In addition, we need a battery plant to even out production, lets assume that we need to store full capacity for 2 hours, or, that slightly less than half of energy produced can be used when generated and rest has to be stored. At battery storage cost of 300 euro per kWh (current cost, roughly based on Chinese Li-Ion large cells) is about 6.6B, so total comes up to 11000 + 6600 or 17600B. It is about double the cost to nuclear. However, cost of panels can go lower, in particular when you go and buy 11B worth of panels and installation stuff as one deal. Li-Ion battery technology cost is dropping and likely drop to less than half within next few years, in particular with volumes involved. If there is hydro or pump power plant possible, it will be vastly cheaper. The plant will take of about 7 * 8 km space for the panels, but any junk land will do, drier desert being the best. Wind is roughly comparable to solar, can be slightly better in terms of power factor if the site is on open sea. Unfortunately wind tends to prefer locations where people are located and complain about eyesore. Usually wind and solar work well together, sunny conditions tend to be somewhat opposite to windy conditions.

If we would make optimistic assumptions and expect panel and installation cost to go to 0.5 euro per W, and can use hydro or pump power for storage, we are looking at total cost of maybe 6B, which would already be below comparable nuclear plant cost. Likewise, if more of the power can be stored or used at peak times, for example, by smart charging of electric cars and running air conditioners to store the energy as heat or cold, we are much better off. For example, 1 M Nissan Leafs or 250 000 Tesla Model S's would do nicely. However, this will require beefier grid to transfer the power during peak production times as it effectively moves storage to consumption location.

The comparison is unfair if the nuke plant is intended for consumer power rather than industrial use, as building that expensive plant needs to be run at full tilt all the time to pay back the investment. If that is not the case, you will needs storage for nuke plant as well, for the opposite reason to solar. This would also make the costs closer to each other, as storage can be quite expensive, if no hydro is available.

Above comparison ignores cost of running the plant. For Nuclear, cost of uranium (etc) is relatively low. Likely larger costs would be insurance if nuclear plants would need to pay that, long term storage of waste, personnel. Currently nuclear plants do not have real insurance, and any disaster of any notable size comes from taxpayer's pocket, at least in European market. For solar, the panels need to be cleaned, and may need upgrading if we would be talking about similar operational life, say, 80 years. Upgrading might increase production, as we might have, within currently given warranties by panel producers (30 years), more efficient panel technology. If Li-Ion is used for storage, it will need replacing with current technology for maybe every 10-30 years. However, batteries can be recycled and within 10-30 years there is likely major technology and cost progress. It might also be possible to locate the plant so that we would get better than 3.5 power factor, again improving the competitiveness of solar production. I cannot estimate how much upgrade work a nuclear plant needs, likely replacement of turbines sometimes, worn out generators, etc.

The above nuclear plant projects have been commercial disasters for Areva, being 2.5 times over original budget already. It might be possible to build cheaper plants. For example, Russians have more cost effective plants, with some added perceived risk.

One factor I would think is important is that solar power can often be generated in the location of consumption. This avoids costs of grid expansion, and if battery systems are installed at the same time, it will increase energy reliability, as house could switch to battery power at any grid problem.

Comment: Re:Bad news for ecologists--new license needed (Score 1) 136

by hsu (#46347777) Attached to: Major Scientific Journal Publisher Requires Public Access To Data

The whole point of science is creating new information, and digging further into raw data, correlating with other data, and finding relationships and further information is very important. Monopolizing the data for one party will reduce amount of research which would benefit from that particular set of data, as there will not be anyone beyond other original creators of the data set being allowed to work on it. Keeping one to yourself might be short-sighted benefit of getting another grant, but it definitely is against public interest. If the grant system benefits people who keep their data secret, the system is completely broken.

Comment: Re:What the (Score 1) 207

by hsu (#46308977) Attached to: Chevron Gives Residents Near Fracking Explosion Free Pizza

It is not about testing for gas in the well, the issue here is the fracking fluid, which, courtesy to excluding the fracking companies from environmental protection, contains number of poisonous or carcinogenic substances. There is no way to get that stuff out from the ground once it is there, and it will slowly move around and spread with groundwater movement. If they just used water and sand, the issue would be just CO2 emissions which can at least be mitigated by plant life, but as it is now, the long term effects are destructive, and profit-makers will leave the mess to others to clean up. This would be equivalent of allowing nuclear industry to dump the the used fuel to rivers and sea and leave any possible accident costs to taxpayers. Oh, wait...

Comment: Re:Not Really (Score 1) 410

by hsu (#46281993) Attached to: Obama To Ask For $1 Billion Climate Change Fund

Solyndra failed on bogus technology, not on China pre-fixing the market. Solyndra was effectively claiming that lower efficiency thin film panels would somehow magically work great when formed in tubes. Calculate the physics, and it is obvious that there is no energy gain, only additional cost. The investment decision was broken, as any competent analyst should have done the simple math to figure this out. Solyndra's own published numbers, cost per W figures, for example, which were non-competitive to start with. Their cost was way above marginal cost of normal panels with higher efficiency, so electricity could not have been produced profitably with their panels, according to their own projections.

This "China subsidy" card is one I have hard time understanding. If we get the benefit, why it is a problem? Europeans first sold Chinese and other countries solar panel plants (100+ plants claimed by one European company alone), which were efficient and could produce good quality panels for low cost. Then we buy the panels they make in those factories for zero (or claimed negative) profit, essentially Chinese subsidizing our economy again. In addition, this will be net energy gain for us. Panels produce more energy than making them consumes, so we get energy from Panels the Chinese effectively paid for us, avoiding some need of import energy or generate energy from fossil fuels. This is perfect colonialism, sell them tools and reap benefits of those tools, pulling money in three ways. We should do more of this.

Chinese may copy and import technologies we sell to them, but by the time they are capable to high quality and competitive technology, they will no more be cheap labor, and the cost levels will not be that different any more. China will be on par, and highly competitive, and they will be part of innovation, but that is unavoidable. No amount of protectionism will avoid it, rather it will protect us from improving efficiency and competitiveness. Japan is a good example of this, they took a their position in the world market, but are now economically in similar position as most western countries, with no more competitive advantage than efficiency or innovation allows. People cost and standard of living has mostly equalized already. The worst thing West can make to our own standard of living is to be inefficient and stop innovating and taking risks.

Comment: Re: Sure, why not? (Score 1) 410

by hsu (#46281543) Attached to: Obama To Ask For $1 Billion Climate Change Fund

Novelty of the rich? Used Leafs are around 20 - 25k and at least in European market the prices are often competitive to similarly equipped gas cars. There is some price difference for new cars, though subsidies or tax differences make up most of it. Savings depend on country, for me they are several k per year, and this is in place which has no subsidy other than cheaper buy tax for the car, and only benefits are cheaper parking and some free charging opportunities. If you finance your car buy, cost savings will make up the difference. If you pay all cash upfront, you might want to calculate the cost factors for your case, it still might be pretty short payback for extra investment.

Impractical depends on who is the target. I did not have to change driving habits in any substantial way. The car is more practical for what I use it for, ie. city driving than my gas car. There are plenty of people in the "sub 100km per day, can afford 20k" or "have two cars and it is used for city driving" brackets, so claiming ev's impractical is not really true, they are practical for quite substantial proportion of the population already, even if we are in the first generation for most manufacturers. Obviously there are people for they are not practical yet.

Priced out of range: there is a used car market being developed rather quickly as the first cars sold come to circulation. If you cannot afford 35k for new Leaf, you can likely get a used one for 20-25k already (that is well-equipped 1 year old car). Also, the difference between gas car and electric with same equipment is low, at least in Europe, as EV's tend to be better equipped, by magic of automotive goodies priced by value rather than cost of them. For me penalty of buying an EV was negative as I did some shopping around. I would not have been able to get gas car as well equipped for the same amount of money. The gadgets made the difference in my case.

Comment: Re:Cellular is the business model (Score 1) 424

by hsu (#46281165) Attached to: Time Warner Deal Is How Comcast Will Fight Cord Cutters

There are examples where having one company take care of physical infrastructure (fiber network, or coaxial in cable), and providing it to anyone who then run electron or light over it, working very well to consumer advantage. One example could be Stokab, which pulled Stockholm city in Sweden some ten years ahead most other places in the planet in terms of broadband connectivity (Ethernet to home ten+ years ago, 100Mbps for 10e/month, etc).

Stokab model is utility, and it is by charter not allowed to do anything else than dark fiber.

http://www.stokab.se/Documents...

Regulation does not work. The operators who run other businesses can always cross-subsidize between their businesses, and no regulator can effectively prove that. Regulation does not force the operators to be efficient or innovative either. With no competition, they do not need to be. And screwing competition is almost always easier than making better products, when your motivation is keep your salary and bonuses rolling and you could not care less of public benefit and innovation. Even if operator is forced to sell infrastructure, they can allocate costs and work force to infrastructure department, and to make everything possible to hurt competition and keep the prices high. I have long experience on this, we launched first commercial ADSL service in Europe and run a competitive operator in relatively progressive environment. The only solution I see working (by proof of success story) is having complete separation at passive-physical boundary, such as Stokab model.

Comment: Re:Dead end (battery swap) (Score 1) 191

by hsu (#46280761) Attached to: Elon Musk Says Larger Batteries Might Be On the Way

While I believe that battery swap idea is possible and such fears might be possible to alleviate, by guaranteeing getting "your" battery back when returning as Tesla says, it is commercially difficult concept.

Here is some math: 1 Tesla S battery stores approximately $15 worth of electric energy (number out of hat). The process takes 2 minutes, and they could have it in a very central location and could have 50% utilization rate during daytime (battery changed every 4 minutes during 10 business hours), total of 150 swaps per day. The battery wear could be assumed to be large as batteries are deeply cycled, so lets assume that they can be used for 5 years and they cost 20k a pop (investment cost today). Assume that the swapping system costs 1M per site (there won't be many of those, so development cost has to be shared with few sites, and it is rather complex system). Assume 10 year lifetime, by then we will have batteries with at least double capacity and the driver will need sleep before battery runs out (even if one would not see that happening, anyone doing business decision on this will account for that risk). The capital cost comes to 700k per year plus return on capital requirement of 5% (low) 200k = 900k. To break even on this one the battery swap would need to cost 16.5$ + energy. That, obviously assuming that the above numbers would not be optimistic, there is a market for such thing in a compact enough area and with enough Tesla S's who want to drive 800km per direction per day to feed it. I would think that this might be possible concept for, say, Taxis in a very large city, or long distance trucking, but I just cannot make a lucrative business proposal out of it for normal cars. Even highly optimistic figures would just make it break even, and it is a very small niche.

Tesla S 85 can already do around 400km per charge, which will take 4-5 hours to drive. Other than 24 hour racing I cannot imagine why any normal person would not feel like having a lunch or other food break every 4-5 hours. Most road safety organizations in Europe recommend having a break every hour or two. Other than very high speed run through Germany on unlimited Autobahns, benefit from drop of recharge time from 1 hour to 2 minutes is not that large, as gas cars will still need 2/3rd of the stops to gas up, and the difference per stop being that Tesla owner needs 1 hour stop instead of 15 minutes. Gas driver will still need top himself up and visit restroom, even it they eat while driving (I think eating sandwich at 200km/hour is a safety risk, and likely illegal in Germany). There are few people (mostly in Germany) who actually have any real time benefit. Would they pay substantial extra for that? Unlikely. Those very few people will get a large diesel car for intercity driving and use a city car such as Volkswagen Up electric for city driving instead. For them, it makes more sense today. The economics come even better for electrics in countries other than Germany, as top speed limitations will make electrics more competitive by making charging stops smaller percentage of the total travel times, as well as allowing longer per charge trips due to lower energy consumption per km.

My conclusion would be that battery swap is technically perfectly possible, but unlikely to be commercially viable.

Comment: Re:Obsolete: No but only in empty places (Score 1) 734

by hsu (#46061683) Attached to: Will Electric Cars and Solar Power Make Gasoline and Utilities Obsolete?

I bought a Nissan Leaf few months ago. The primary reason for me, as an engineer, was efficiency. It is just stupid to use something which wastes most of energy you put in it in a ludicrously complex engine. The other important arguments are consequences of this.

- Ecology: More kilometers per unit of energy means less pollution. Consequence of efficiency.

- Lower cost of driving: More kilometers per unit of energy costs less money. Simpler servicing due to fewer parts. Both consequences of efficiency and simplicity. My Lexus GS cost me about 8000 euro per year on average (gas in Europe is pretty expensive). The leaf costs less than 2000 euro per year. I only use the Leaf for city driving, but that is more than 2/3rds of my use. Both numbers include insurance, energy to run it, servicing, and taxes. In addition, Leaf saves me additional money, as I get free parking and charge in Helsinki city center, where parking costs easily 6-8 euros per hour.

- My health improves and I save additional time as I no more need to spend 15 minutes cursing and cooling down after paying 120 euros for filling the gas gar.

- Quietness: Generating noise costs energy, electrics do less of that. Consequence of efficiency. Very important for me. The only problem is that now I get irritated by other cars making noise which was previously hidden by my own vehicle. Leaf makes some electrical whine, but it is way less disturbing.

- Good acceleration: Plenty of instant torque at slower speeds. Consequence of efficiency. Leaf is definitely not a sports car, but acceleration in city driving is on par with GS. It will loose to GS at higher speeds, but I bought the Leaf for city driving.

There are other lesser arguments which are not efficiency based.

- No smelly gas to handle. They will need to invent less smelly washer fluid though.

- Car is always filled up. I am saving time because of not having to go to gas station every now and then. Plugging and unplugging the car takes max 20-40 seconds per day extra during summertime. In wintertime it takes extra 0 seconds as I would also plug in my gas car to run the block heater. I sometimes quick charge on longer travel days, but the quick chargers are mostly right next to a place I can pick up a cup of coffee or groceries, so amount of time waste is around 20-30 seconds. I have visited a gas station once to get distilled water for my humidor. They had run out.

- Remote control of heating/cooling. Today was -17 degrees Celsius. The car was +20 when I left for work, and +20 when I started back to home. You can get this for gas cars, so not quite a difference, but having it standard was one less problem.

- Good feel of not using totally idiotic and obsolete technology.

- Egoistic feel of being ahead of other people.

- I also saved money when I bought the car, as I found a used demonstration car of a Nissan dealership in Spain. For the money I paid I could have gotten smaller or same size gas car with same age and km driven, with less gadgets and features in it. So, the payback time of buying electric become negative for me. Took a bit of effort to shop around, though. Driving the car back to Finland was fun, so I did not count it a cost, nor the about 100 bottles of wine picked on the way from shops and wine yards. I highly recommend looking at used Leafs or other electrics if you wish to get in to electric driving on budget.

Problems I have noticed:

- I kept the Lexus for longer trips I assumed would be likely every two weeks or so. I haven't driven it once for two months I have had the Leaf. When I borrowed the Lexus to a friend, it would no more start, as the battery was dead. Apparently I would be better off renting or car sharing whatever cars I need for longer trips. I can do plenty of that with the 6000 euros of annual savings.

- We do not yet have plenty of electrics here yet, so every week or two I have some curious guy asking questions about the car. I does not bother me too much, and I can always so sorry if I'm too busy. Leaf looks like a any normal car, so most people do not pay attention.

- I waste some time writing this article in Slashdot.

Note:

I am privileged to live in a city which is compact enough that Leaf's range is adequate to reach most places, as well as having several quick chargers around in case I would need one. I normally charge to 80%, as that seems to work for most days. I assume the range might be more of an issue in larger cities. For me, it has been better than I thought, even with my high early expectations.

Comment: Re:Fucking rednecks (Score 1) 1030

by hsu (#45512447) Attached to: A War Over Solar Power Is Raging Within the GOP

Everyone seems to conveniently forget that Chinese photovoltaic industry is built with mostly European technology. European companies had or were delivering some 150 turn-key factories to China, India and other countries around 2009, and they made claim that with their production lines could produce panels at very low cost. European companies had problems because they had older and less efficient production methods. It is a bit like selling tools to gold diggers, it makes more profit than digging the gold. Thin film people can beat the cost per Watt, but the panels are already so low cost that installation, electronics, wiring and support structures are substantial part of investment, so efficiency becomes important.

The EU-China trade war is typical trade war, the party (EU) which wants to stop the flow of cheap panels is loosing by getting its demands met. A low cost solar panel imported to EU is making net profit to EU, as it produces much more energy during its lifetime than was made in its production. Even if Chinese government subsidized Europeans making cheaper energy, it would be a win for Europe. EU wants China to get more of that profit, at cost of allowing European Solar industry to become even more uncompetitive by avoiding necessary restructuring and innovation.

Comment: Re:Let's compare the two (Score 1) 559

by hsu (#43885269) Attached to: No, the Tesla Model S Doesn't Pollute More Than an SUV

If you take binary yes or no, both can be renewable ways of generating motive power.

However, it is better to use numbers, as renewable energy, at least the one most widely available, is all solar based. You take solar panel, and turn sunlight into electricity at panel efficiency of around 20% and system efficiency of around 20-30% off that for grid and conversion losses, and loose further 30% in the electric car. Or you plant some plants, algae, or other biological stuff, and have them turn sunlight into biomass at conversion efficiency from 3%-6%, and then, at use that to refine some biofuel, loosing some 10-50% of energy, loose maybe 10% in transport, and then drive your ICE car, loosing 80% there. Solar+electric cars is approximately 50 times more efficient. That is, take a hectare of land, and it will produce energy for daily 50km commute for close to 1000 cars, or about 20 ICE cars running on renewable biofuel.

Above 3-6% efficiency for photosynthesis is theoretical number, not really see in nature.

Above 20% efficiency for solar panels is current high quality consumer panel efficiency, grid losses are measured losses in grid where I live (Finland), and electric car efficiency is average efficiency claimed for most electric cars (converted car can be a bit lower).

Hectare example was calculated on solar vs. palm oil, taking numbers from palm oil plantation press releases. With palm oil, world energy need cannot be met even if we use most rain forests and most arable land. Photosynthesis requires water and good conditions as well. You can plant Jathropa in desert, but the efficiency is close to zero.

Solar panels can be installed on desert or rooftops, and as you need 1/50th of space, it actually is feasible.

In some locations, you may have other effectively renewable sources of energy, such as geothermal. Obviously, in most cases that usually drives electricity generation.

"Consistency requires you to be as ignorant today as you were a year ago." -- Bernard Berenson

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