Category Archives: electricity

Expiring the Internal Combustion Engine Car

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The US state of Washington has decided to ban sales of new cars with internal combustion engines (ICE, gasoline or diesel) by the year 2030. That is five years earlier than in the state of California.

There are two issues to overcome for a switch to battery electric vehicles (BEVs): supply and charging. Two common worries however will not stand in the way of BEVs replacing ICEs: cost and range. Let me explain.

Battery cost per kWh has been dropping for decades and this trend is expected to continue. THis is highly significant: Most parts of a BEV car other than the big battery cost either the same as in an ICE car or they’re cheaper. As a result, the cost of batteries will stop being a major obstacle to adoption of BEVs years before the end of the decade.

The same is true for range. Cheaper batteries mean BEVs with more capacity will become affordable. The higher the capacity, the more km of charge can be replenished in a given number of minutes. For example, a Nissan Leaf with a 40 kWH battery will fast-charge from 0 to 80% in 40 minutes. The Volkswagen ID.4 First Edition with an 82 kWh battery (of which 77 kWh are usable capacity) will go from 5% to 80% charge in 38 minutes, essentially double the charging speed (kWh added per minute) for a battery with twice the range. If you can add hundreds of km of range in the time it takes you to use the toilet and get a cup of coffee then BEVs will be just as viable for long distance trips as ICE cars.

By the middle of this decade there is likely to be a wealth of different battery electric vehicle models on the market, with even BEV laggards such as Toyota, Honda and Subaru having joined in. Production could increase to about 50% of new sales of several large makers (e.g. GM, VW). It will have to scale up further, with the necessary increase in battery production capacity, by the end of the decade to make this happen but it seems eminently doable. Right now, the major bottleneck to ramping up production is not lack of demand but limited availability of battery cells. Every big car maker getting into BEVs will have to build Gigafactories churning out battery packs, or team up with battery makers who make these huge investments.

The more BEV there will be on the road, the more the impact on the electric grid becomes an issue. If you have a car that can cover 300 km or more on a full battery and you can charge at home every night then most likely you will almost never have to seek out a charging station, unlike drivers of ICE cars who regularly will have to fill up at a gas station. BEVs parked in a driveway or garage with a nearby wall socket are much easier to accommodate than cars currently parking in the street or on parking lots, who will require capacity at paid public charging points, which are more likely to be used at daytime. The grid has plenty of capacity for off-peak charging (e.g. overnight), but if a lot of people want to do their charging at superchargers or other fast charging points, this could require an upgrade in generating and transmission capacity to cover a higher daytime peak load. Vehicle to grid technology would help to make this more manageable, as cars sitting idle in a driveway could provide spare power for the few cars doing the odd long distance trip.

In any case, I see a date roughly around 2030 as the Goldilocks target for a phase-out of ICE-powered new cars. For high income countries this goal is neither too unambitious nor too unrealistically aggressive. Japan’s goal by contrast for a phase-out by the mid-2030s that still allows hybrid ICEs like the Toyota Prius after that date is quite unambitious. By setting the bar that low, prime minister Suga pleases Toyota, as expected, allowing it to keep selling dated technology in Japan that they will no longer be able to sell elsewhere. That puts Japan in the company of developing countries, which will most likely continue using ICE cars exported from rich countries for years to come.

The sooner rich countries switch to BEVs, the shorter the long tail of CO2-emitting ICE cars still running in poorer countries will be.

Releasing Tritium-tainted Water from Fukushima 1

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The Japanese government has approved a plan by Tepco to release more than a million tons of water stored in tanks at the site of the Fukushima 1 nuclear power station. The water is supposed to be gradually released into the ocean starting two years from now.

Currently about 1.2 million t of contaminated water are stored on site, an amount that is increasing by about 170 t per day. Tepco is expected to run out of space at the end of 2022. Water is being injected into severely damaged reactors on the site to cool the remains of nuclear fuel left inside. It leaks back out, mingles with ground water that seeps in and is then purified through a filtration system called ALPS. This removes most of the radioactive contamination, but leaves tritium, a radioactive isotope of hydrogen which can not be chemically removed from water. So it ends up in the storage tanks.

Proponents of the release argue that tritium poses little hazard in small quantities. Radiation from tritium is so weak, it only travels for a couple of mm through air and it is stopped by the dead cells on the outside of human skin. Even if ingested it does not accumulate in the human body.

The water released will be diluted to levels so low it would meet drinking water standards in Japan and in other countries. Opponents fear an economic backlash against local fisheries or argue in principle that Japan has no right to contaminate the Pacific ocean, which is not just their territorial waters but shared by many other countries.

Proponents call such criticism hypocritical, given that many other countries, including the Republic of Korea, routinely release tritium into the ocean from their own nuclear facilities.

The issue is complicated. First of all, whether the danger from the water release is real or exaggerated, fishermen will suffer economically because consumers will end up avoiding fish from Fukushima more than they already do, even if it was safe to eat. If the release is unavoidable, the fishermen should receive compensation for their economic losses. That is only fair.

The truth about the water is not black or white. The 1.2 million t of water that has accumulated over the past decade was treated in different ways at different times. Some may indeed contain only those low levels of tritium as a contaminant, but other tanks will hold water that still has significant amounts of caesium, strontium and other dangerous isotopes that unlike tritium can accumulate in organisms and pose long term hazards. More purification and testing will definitely be needed before a release can take place. As Motoko Rich and Makiko Inoue reported for the New York Times in 2019:

Until last year, Tepco indicated that with the vast majority of the water, all but one type of radioactive material — tritium, an isotope of hydrogen that experts say poses a relatively low risk to human health — had been removed to levels deemed safe for discharge under Japanese government standards.

But last summer, the power company acknowledged that only about a fifth of the stored water had been effectively treated.

Last month, the Ministry of Economy, Trade and Industry briefed reporters and diplomats about the water stored in Fukushima. More than three-quarters of it, the ministry said, still contains radioactive material other than tritium — and at higher levels than the government considers safe for human health.

The authorities say that in the early years of processing the deluge of water flowing through the reactors, Tepco did not change filters in the decontamination system frequently enough. The company said it would re-treat the water to filter out the bulk of the nuclear particles, making it safe to release into the ocean.
(New York Times, 2019-12-23)

Long term there is no real alternative to releasing the water. Once its radioactivity has been reduced to only tritium, dilution and disposal at sea should pose little risk.

The challenge however is that Tepco and the government have a public trust problem, at home and abroad. How do we know the water released will be as clean as claimed?

Any release process needs to be transparent and independently verified to make sure there are no shortcuts or other shenanigans.

See also:

Germany Reaches Renewable Energy Milestone

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The drop in demand for electric power due to the Covid-19 pandemic helped Germany reach an environmental milestone in 2020: For the first time more electricity from renewable sources was fed into the German grid than from fossil fuels and nuclear combined.

50.5 percent of the net electricity production came from wind, solar, hydro and biomass vs. 49.5 percent from fossil or nuclear. Wind power alone accounted for 27 percent of all electricity, more than brown coal and hard coal combined (24.1 percent).

2020 numbers for Japan are not yet available, but in 2017 renewables excluding hydro power accounted for only 8.1 percent of the Japanese electricity production, with hydro providing another 7.9 percent. 39.5 percent came from LNG, 32.7 percent from coal 8.7 percent from oil and 3.1 percent from nuclear.

Japan’s power generation plan for FY2030 foresees only 1.7 percent for wind power, 7 percent for solar and an overall share for renewables (including hydro power) of 22-24 percent of the total. That is less than half the share that Germany achieved in 2020, a whole decade before Japan.

Test-driving a Tesla Model 3 in Tokyo

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Recently my son Shintaro and I went to the Tesla showroom in Aoyama, Tokyo to take a Tesla Model 3 for a test drive. I wanted to see for myself how this electric vehicle compared to my almost 12 year old Prius hybrid and to be able to compare it to future EVs from other brands that we may eventually consider.

I’d noticed an increasing number of Teslas around Tokyo, though they’re still far rarer than around the San Francisco bay area. Given that much of Japan is densely populated, range anxiety (an often cited reason for slow electrification) should be less of an issue here compared to the US, particularly with cars that already have over 400 km of range.

I love the practicality of the rear hatch of my Prius that allows me to carry two road bikes without disassembly by simply folding the rear seats. The Tesla Model 3 has a much less accessible trunk, which pretty much rules it out for me. The Model Y will be more practical, but is also even bigger. Apparently it won’t be available in Japan until a year or two after it starts shipping in the US this month (March 2020).

Tesla’s models are quite large by Japanese standards, with implications for parking and for driving on narrow back streets. For example, these are the dimensions of the Tesla Model 3 vs. the current generation Toyota Prius (XW50):

Length: 4690 / 4570 (+120 mm)
Width: 1850 / 1760 (+90 mm)
Height: 1440 / 1470 (-30 mm)

Exact numbers for the Model Y aren’t available yet, but it’s expected to be about the same width but about 1600 mm tall (160 mm taller than the Prius).

The test drive was an unusual experience by Japanese standards. Somebody had mentioned that the dealer experience with Tesla is more like visiting an Apple store than a traditional dealer showroom. I’d say the difference was even greater.

Customer service expectations in Japan are incredibly high and that is probably one factor for Tesla’s relatively sluggish sales here, see a recent Japan Times article.

Shintaro had tried to make the reservation online and was promised a callback within 48 hours, but that never happened so he had to call again to fix up an appointment.

Even when I take my Prius to an oil change at a local gas station, I’ll be served a cup of coffee while I wait. By contrast, when we visited the Tesla showroom to evaluate a JPY 5,100,000 (USD 48,000) car, all we received was a business card of the sales person. They don’t even give you paper brochures. You can look it all up on the website, right?

Before the test drive they took photo copies of our drivers licenses. We were instructed not to take any pictures and to follow the rules of the road. We would be liable for any incidental damage to the car during the test drive. Then we got into the car parked by the roadside outside the showroom, first as passengers, then later taking turns driving it around Akasaka.

I liked the seats, which were nice and firm. The acceleration when you put your foot down is amazing. It feels like a big car but with enough power for its weight. Getting back into the Prius later, it felt quite light by comparison, by which I don’t mean acceleration but it simply feels like a lot less metal being moved around. It tips the scales at about 280 kg less than the base Model 3 (1335 kg vs. 1612 kg).

Some of the controls took some getting used to, such as the lever action of the indicator stalk (which is on the left unlike in Japanese cars) or putting the car into park or into drive with the right stalk. Much of the demonstration involved showing the use of the center screen and its user interface. Many of the functions of the car, such as the electrically assisted steering or the regenerative breaking can be tweaked there, to change the feel of the car.

Headroom in the Tesla was good but personally I don’t much care for the glass roof. In a roll-over accident I would feel safer with a steel roof, but maybe those are not so likely with the low center of gravity afforded by the floor-based battery. The car interior felt overheated when we got into it and no fan was blowing, but I only asked about fan control towards the end of my driving portion. In any other car I would have easily figured it out on my own.

Checking out the trunk and the “frunk” (front trunk) after we got out of the car, the limited access for bulky luggage from the rear was quite a contrast to our Prius, in which we regularly move large items from a DIY center or bicycles for cycling tours far from Tokyo. The Model Y will address that, but it’s also 160 mm taller than the Prius on top of being 90 mm wider like the Model 3. That’s more air resistance and more kWh used to overcome it. That’s one thing I love about the Prius, it offers all this interior space despite being compact and efficient on the outside. 🙂

The width would already make a Model 3 or Model Y a very tight fit in our driveway. We would also have to figure out if there’s enough clearance around the car to plug in the charging cable for overnight charging.

In summary, Tesla’s range of cars is not an easy sell for me as a Japanese customer. While they have great technology, some of the design choices are not a good fit for Japan and the customer experience when dealing with the company (especially given the price range) will not match a lot of cultural expectations.

UPDATE (2020-03-19):

Size information has finally been released for the Model Y. These are the exterior dimensions compared to my current Prius:

Length: 4751 / 4570 (+181 mm)
Width: 1921 / 1760 (+161 mm)
Height: 1624 / 1470 (+154 mm)

Given the width and height it looks like it has roughly 20% more frontal area than the Prius which will impact its air resistance and hence energy usage at freeway speeds.

Toyota is yielding the future to Tesla and other EV makers

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In October 2019, Toyota along with General Motors and Fiat Chrysler sided with the Trump administration in its effort to strip the state of California of its ability to set tighter vehicle emission standards than set by the Federal government. In July 2019, several other car makers including Ford, Honda and Volkswagen had sided with California.

This seemed a very odd move for a company whose iconic Prius hybrid was once seen as a way for people ranging from middle class families to Hollywood stars to show their green credentials. Toyota seems on the wrong side of history now.

I also drive a Prius which I bought almost 12 years ago. When it came out, it was way ahead of everything else: Three times as fuel efficient but more spacious and more reliable than my Audi. It wowed me when I first saw one and later when I first test-drove a friend’s. As an engineer I appreciated the clever technology behind it and as a family man I could rely on it for affordable transport.

However, if I were to buy a car now, I’d have a hard time making up my mind. If Tesla had designed its Model 3 as a mid-size hatchback (like the Prius) instead of giving it a trunk, the choice would be easy. Tesla seems set to address that criticism with its forthcoming Model Y, which will be like a slightly larger hatchback version of the Model 3. If Toyota had redesigned its Prius as a battery electric vehicle (BEV) with at least 300 km of range, the choice would have been even easier. The problem is, Toyota isn’t going to do that and I think I understand why.

I have talked to Toyota dealer sales representatives who came to sell me a new Toyota and when I mentioned about electric vehicles, they kept telling me the time wasn’t ripe for that yet, that infrastructure was too spotty and range too short. I would be better off getting another hybrid as the next car. And Toyota has many hybrid models.

This is precisely the problem: Toyota kept enhancing the hybrid drivetrain of the Prius, improving fuel economy with every new version. Now many different models, from the Toyota Aqua / Prius C to the Corolla Hybrid to the JPN Taxi basically all use the same family of engines, gearbox, battery, inverter and other electric systems. This has kept development costs low and maximized economic gain from the numerous patents that Toyota has received for the Prius.

Meanwhile, Tesla appeared on the scene as a complete outsider and took a radically different approach. By going for an all-electric drivetrain they don’t need an Atkinson-cycle internal combustion engine (ICE), an electrically controlled planetary gear transmission and many other mechanical parts that make the Prius family unique. They just need a bodyshell, an electric motor/generator, inverter and battery. For the first models the battery was basically built up from the exact same “18650” cells that power laptops and the bodyshell for the Tesla Roadster was bought in from Lotus.

Batteries for the automotive market are made by specialized suppliers such as Panasonic and LG instead of being based on in-house designs and intellectual property such as ICEs or gearboxes. Motor/generators and inverters are much simpler and less proprietary than ICEs. The basic technology for inverters used in BEVs and the electric part of hybrid drivetrains has been around since before the 1960s. Toyota engineers got the inspiration from the electrical systems used in bullet trains (shinkansen) that launched before the 1964 Tokyo Olympics.

If current owners of conventional or diesel cars replace their aging vehicles with hybrids then Toyota and its stable of Prius and cousins will do very well. If people however take a good look at the ecological realities of the 2020s and beyond, they will see that the sooner we can stop pumping more CO2 into the atmosphere, the less catastrophic our future will be on this planet. If we still drive cars, they will have to run on renewable energy sources, which hybrids can’t do (except plug-in hybrids for relatively short distances).

This raises a second issue: Toyota has been betting on hydrogen as the fuel of the future. Its Toyota Mirai runs on compressed hydrogen (H2), which is converted into electricity in an on-board fuel cell. This gives it a range of about 500 km between refuelling.

If Toyota were to sell BEVs with ranges of 300-450 km, this would undermine the rationale for hydrogen cars which need a completely new infrastructure for refuelling. Each H2 station costs millions of dollars and the fuel is expensive.

The most economical way of making hydrogen is from natural gas or coal, which releases greenhouse gases. Though one could make hydrogen through electrolysis (splitting water into hydrogen and oxygen using electricity), because of inefficiencies inherent in this process, this would actually consume about three times more renewable electricity than covering the same distance by charging/discharging a battery. This is why hydrogen will ultimately remain an automotive dead end.

What hydrogen technology basically gives Toyota is a political fig leaf: They can claim to have a path into a carbon-free future that does not rely on batteries (like Tesla and others). Using that fig leaf they think they can keep selling cars that burn gasoline, in California and elsewhere. Perhaps they can hold off moving beyond hybrids for years and years to come. If they can keep selling what they’ve got they may make healthy profits in the short term, but for the sake of the planet I hope this plan won’t work.

I’ve seen this movie before. In the 1990s Sony launched its MiniDisc (MD) player as a replacement for analog audio tapes and recordable alternative to digital Compact Discs (CDs). Then, in the late 1990s MP3 and flash memory came along: smaller, cheaper, more simple. The whole strategy fell apart. Sony could have accepted that MP3 was a superior solution, but that would have then put them on a level with every other audio consumer product maker. Their patents on MD would have become worthless. So they struggled on with trying to promote MD until they eventually had to kill it. From the inventor of the iconic Sony Walkman that had created a whole new market and sold the brand name to billions of consumers, Sony turned into a company that had lost its way. It let newcomers such as Apple with its iPod (which soon morphed into the iPhone) take over the market and consumer mindshare. The rest is history.

So if you’re listening, Toyota: Please build a car as spacious, practical and reliable as the Prius, but without a hybrid drivetrain that still releases CO2 with every km driven. Make it a no compromise battery electric vehicle. Support vehicle-to-grid technology, in which parked cars have an important role to play for stabilizing the electrical grid. Instead of working with fossil fuel companies to turn fossil fuel into hydrogen for thousands of yet to be built H2 filling stations, support expanding renewable power production from solar, offshore and onshore wind, geothermal and large scale storage, which is what we will need for a carbon-neutral future.

Meanwhile, when the time comes to replace my 12 year old car I will look at all the battery electric hatchbacks on the market then. If there is no Toyota amongst them then my next car will not be a Toyota. It’s as simple as that.

The Runway to Hell

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Even four years after the Paris climate agreement, politicians, businesses and consumers are still in denial what this means for our future and what we must do today. At best, we’re all paying lip service while trying to postpone making real changes.

Two examples: Narita airport is planning for a major expansion in flight capacity in the 2020s and Tepco and Chubu Electric Power are trying to open a new coal fired power station in 2023.

One of the greatest concerns behind climate change goals are climate feedback loops, where any amount of additional global warming triggers new causes of global warming. A few examples:

  • If arctic temperatures rise enough for the ground in permafrost regions to thaw in the summer this will lead to CO2 and methane releases from frozen ancient organic matter that starts to rot and decay.
  • Warming oceans may release methane trapped in icy slush as methane clathrate on the sea bed.
  • If summer air temperatures on the Greenland ice sheet rise enough to melt snow during daytime before freezing again, it changes the albedo of the frozen surface to absorb more sunlight and melt again more easily.

So if we want to avoid runaway global warming, we have a very tight CO2 budget that we can still release before the world has to run on 100% non-fossil energy sources.

What we would need is a moonshot-like project, with our brightest minds and financial resources focused on switching all power generation to non-fossil energy, expanding it to take over from other uses of oil and gas such as transport while minimizing release of CO2 outside of power generation. That means not just electric cars and trucks but also fewer cars, less air travel, no more deforestation, minimal consumption of cement and steel and more recycling.

While the Japanese government has formally committed itself to fighting climate change, the reality looks different. Last year the Narita International Airport Corp., government ministries and local government agreed to a plan to increase annual takeoff and landing slots from 300,000 to 500,000. To this purpose, a 2,500 m runway will be extended to 3,500 m to handle bigger planes and a third runway of 3,500 m will be built in the 2020s. Currently, there is no practical alternative to kerosene-based jet fuel. More flights and bigger aircraft mean more CO2 emissions from fossil fuel. Instead of making it possible for more people to fly more often, we should be looking for ways to discourage and avoid flying wherever possible.

JERA, a joint venture between Tepco and Chubu Electric Power is trying to build a coal-fired power station at Kurihama near Yokosuka, with plans to start operating in 2023. Coal is the most carbon-intensive of all fossil fuels. One kWh generated by burning coal even in the most advanced coal-fired thermal power stations releases about twice as much CO2 as the same amount of electricity generated from a combined cycle gas turbine (CCGT) power station running on natural gas. With a limited carbon budget it makes no sense to burn any coal if we still have gas. If we really still must expand fossil fuel power generation (and we probably don’t in Japan), coal is by far the worst choice of all fossil fuels available!

Instead of expanding airports and building coal power stations, we should expand offshore wind power and geothermal energy while raising taxes on air travel, for example by taxes on jet fuel. A recent International Energy Agency report estimated the worldwide potential for wind energy production at 11 times the annual electricity consumption of the world. Japan has almost completely blocked offshore wind power. It has a huge Exclusive Economic Zone (EEZ), yet in 2018 Britain’s installed offshore wind power base was over 120 times that of Japan, Germany’s about 100 times and China 70 times. Even Belgium which controls only 0.5% of the North Sea had 20 times more installed offshore wind power capacity than Japan in 2018.

Some air travel can be shifted to trains or to less energy intensive ships. Eventually we will develop technology to fly airplanes with non-fossil fuel, such as methane produced from CO2 with renewable electricity in reverse fuel cells though that won’t be cheap or particularly energy-efficient. But until then we need to make hard choices that take us closer to our goals, not further away from them.

Future generations will struggle as coastal land where hundreds of millions of people worldwide currently live or where they grow food will disappear in the sea as warming oceans expand and glaciers melt. They will have to deal with it.

Whole countries will disappear in the next couple of centuries, including the Netherlands and Bangladesh. The same will happen to most of the ten largest cities in the world. The sea level rises projected until 2100 are by no means the end of the story: Sea level rises for several centuries to come are already locked in with the emissions of the last 200 years. The last time this planet had more than 400 ppm of CO2 in its atmosphere (as opposed to 280 ppm before the industrial revolution) was 3 million years ago, when sea levels where 20 m higher than today. So that’s going to happen again, even if we stopped burning all coal, oil and gas today. But because we are still going to keep doing that for a number of years or decades, the ultimate sea levels will be even higher than they were then.

Maybe in some ways it’s easier to speak truth if you’re a 16 year old school kid, not a politician who wants to get campaign finance from friendly businesses or to get reelected by voters who still want to fly on vacation to Thailand, or a business leader trying to please shareholders instead of saving the planet. But reality is reality, even if we look away. We, or our children and their children, will have to face it eventually and it will be what we make it today.

Water Abundance XPRIZE – Do the Numbers Add Up?

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On October 22, 2018 a US$1.75 million prize was awarded to two companies for a way of providing abundant water at a price of no more than $.02 per liter using renewable energy.

The technology developed by the Skysource / Skywater Alliance condenses humidity from the air using electrically powered compressors. It’s basically the same process as in a domestic air conditioner unit that has water dripping out of it, except that the Skywater units will filter and then sterilize the water using ozone. Condensation through a compressor is an energy intensive process.

There are other processes for generating fresh water from abundant sea water that also have a reputation for consuming a lot of energy. Desalination is used by many coastal cities and regions to top up insufficient ground water supplies. About of half of Israel’s water supply comes from Reverse Osmosis (RO) plants that desalinate sea water from the Mediterranean. Desalination plants also provide about 30% of Singapore’s water supply.

Reverse Osmosis consumes about 3 kWh of electrical energy per 1000 liter (1 m3) of fresh water extracted. If produced from fossil energy sources such as coal, oil or natural gas this energy demand will result in CO2 output, contributing to global warming. If produced from renewable energy, it requires considerable investments in generating capacity on top of the desalination plants themselves.

How does the Skywater process compare to RO with regards to energy consumption? The Skywater website is not exactly helpful, as it present gibberish instead of actual data:

What are the power requirements for the machine?
The Skywater® 300 runs on approximately 7 -10 kilowatts per hour. It operates on 50hz or 60hz and either 208-240V (single phase) or 380-440V (3-phase). This power can be supplied directly or from a generator for portability.

The Skywater 300 is a unit that can generate up to 1100 l of water per day. The above quote was neither written nor checked by an engineer. Note that energy is measured in kilowatt hours (kWh) while power is measured in kilowatts (kW). There is no such unit in physics as “kilowatts per hour”. Whoever uses this term basically doesn’t know what they are talking about! A device drawing one kilowatt of power will consume one kilowatt hour of energy for every hour of use.

Let’s assume they meant a power demand of 7-10 kW (which is the same as 7-10 kWh per hour). That means a daily consumption of 168-240 kWh of electricity. With an output of up to 1100 l, this amounts to at least 150-220 kWh per 1000 l (1 m3). This is roughly 50-70 times more than the specific energy consumption of a Reverse Osmosis plant. Other commercial units of water generators have similar specs. For example the units offered by Water-Gen in Israel are quoted as consuming 310 kWh per 1000 l, or roughly 100 times the power consumption of reverse osmosis units.

Today we’re still a long way from having access such an abundance of cheap electricity from renewable sources that we could afford to use 50-100 times more of it than another proven solution would use. Installing solar panels or wind turbines to power RO plants is expensive and consumes land. Building 50-100 times more solar farms or wind turbines to generate the same amount of water using water-from-air technology instead would make little sense, at least within a reasonable distance of the coast where you could still pipe desalinated water from coastal RO plants.

Water-from-air technology may make sense only in limited areas such as mobile military units in remote areas where cost is no object (but only if humidity is not too low and it’s neither too hot or too cold, i.e. if they’re not deployed in a desert anyway).

On the present evidence, water-from-air technology is far from ecologically benign or economically viable, compared to more efficient technologies available. The first step would always have to be reduced use of conventional water supplies (e.g. better irrigation systems, growing less water intensive crops) encouraged by appropriate pricing and reuse of waste water for other purposes.

Carbon Sink Concrete Snake Oil

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When I was a kid, I learnt that carbon dioxide (CO₂) makes up around 0.3 % (300 ppm) of the atmosphere. Man-made CO₂ output, from burning of fossil fuels to deforestation, has increased this number year after year. In 2013 it first exceeded 400 ppm. Even back in the 1950s, after over century or coal and oil burning, the number was already the highest in 650,000 years. We are still adding CO₂ to the atmosphere every year and the amount being added per year is still increasing. As CO₂ is a heat-trapping greenhouse gas, this has far-reaching consequences. There are dangerous feedback loops that will amplify the consequences, from increased arctic warming from absorbed sunlight due to melted sea ice to increased methane output from melted permafrost regions. Disappearing mountain glaciers will have effects on rivers downstream.

As humanity realizes the dangers from changing climate, from rising sea levels to extreme weather patterns, devastating droughts and wildfires, desertification and failing harvests we need to take action. We will need to cut CO₂ emissions as much as possible as soon as possible, but we also need to look at ways of binding CO₂ that has already been released.

Some people are trying to make a quick buck on this or to deflect consequences from industries that harm the environment. Because of this, be very skeptical of any claims made for carbon sink technologies that aim to delay the phasing out of fossil energy sources (including but not limited to “clean coal”).

A couple of years ago a US company called Calera made headlines with bold claims of a process that could act as a carbon sink for CO₂ from fossil fueled power stations while producing a product that could be used in place of cement. About 5 % of global CO₂ output is from cement production while power stations account for about 1/3 of CO₂ output in the US, therefore this would sound like a win/win situation. The process would extract calcium from sea water, combine it with CO₂ from the smoke stack of a power station and output calcium carbonate (lime stone) as a building material. Calera received funding from ventures capital fund Khosla Ventures and built a prototype plant adjacent to the Moss Landing power station at Monterey bay, California.

The company has always remained fairly tight lipped about how its process would actually work and what its inputs and outputs would be. However, despite the numerous articles that repeated its ambitious claims, nothing much seems to have come off it since.

The fact is, their claims were debunked by two critics, Jerry D. Unruh and Ken Caldeira, but relatively little attention was paid by the media to the inconvenient facts they had pointed out.

Most of the calcium and magnesium dissolved in sea water is either in the form of calcium bicarbonate or magnesium bicarbonate. To precipitate dissolved (Ca,Mg) bicarbonate as solid (Ca,Mg) carbonate, one has to remove CO₂, not add it. Calcium and Magnesium dissolved in the ocean is there because rain water absorbs CO₂ from the atmosphere and then dissolves lime stone and dolomite rock as it seeps down into the ground before re-emerging in springs and rivers:

H₂O + CO₂ + CaCO₃ => Ca(HCO₃)₂
H₂O + CO2 + MgCO₃ => Mg(HCO₃)₂

Precipitating solid carbonate from dissolved bicarbonate reverses the process and thus releases CO₂:

Ca(HCO₃)₂ => CaCO₃ + H₂O + CO₂
Mg(HCO₃)₂ => MgCO₃ + H₂O + CO₂

Fundamentally, calcium and magnesium ions (Ca++, Mg++) in sea water are not a viable option for binding millions of tons of CO₂ as they are already the end result of a carbon-binding process. Turning bicarbonates into carbonates either releases CO₂ or it requires huge amounts of alkaline materials to bind that CO₂.

The truth is, besides CO₂ and seawater, Calera’s prototype plant consumes existing stocks of alkaline magnesium oxide left over from previous industrial uses at the site, but those stocks won’t last forever. If one had to replenish these stocks from scratch year after year, this typically would involve the high temperature calcination of magnesium carbonate, which consumes roughly as much energy and produces as much CO₂ as making cement does.

Calera has suggested a few alternatives in place of magnesium oxide as alkaline process inputs for a full scale production system, but these don’t make much more sense either:

  • Making sodium hydroxide from brine via electrolysis consumes more electricity than can be produced from any power station whose CO₂ this process could clean up.
  • Fly ash from power stations can be a low cost source of alkalinity, but only in the case of relatively carbon-heavy coal and not natural gas. Even there the amounts of ash are far too small relative to the amount of CO₂ to be absorbed from burning the coal. Cleaning up CO₂ from coal using fly ash still leaves you with more CO₂ than burning natural gas without cleanup.

Long term, the cheapest way of dealing with rising CO₂ levels are not carbon sinks, but not producing the CO₂ in the first place. This means reducing energy consumption, a halt to deforestation, switching transport to electricity and producing power from wind, solar, geothermal and other non-fossil energy sources. The sooner we do this, the more livable this planet will remain for its 7 to 12 billion inhabitants this century.

Further reading:

Olympic Hydrogen Hype

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Today’s Japan Times reports that the Organizing Committee of the 2020 Tokyo Olympics is considering the use of hydrogen torches to light the Olympic flame (“Olympic panel mulls high-tech hydrogen torch, pares soccer venues” — JT, 2017-02-27):

“An important theme of the Olympics is how to promote environmental sustainability. We will talk to experts and see how realistic it is in terms of technological development,” a committee member said.

One official said there are still safety and cost concerns, and asserted that there also was a need for a lightweight torch that can be easily carried.

In March 2016, the Tokyo Metropolitan Government announced a project to have the 6,000-unit athletes’ village for the games run entirely on hydrogen power.

The Japanese government is one of the most active promoters worldwide of a so called “hydrogen economy”. It sees the 2020 Olympics as an opportunity to showcase Japan’s lead on hydrogen. Other projects are the construction of a nationwide network of hydrogen filling stations for hydrogen fuel cell vehicles (HFCV) such as the Toyota Mirai, research into shipping liquefied hydrogen from overseas using special tankers and production of hydrogen from lignite (brown coal) in Australia for export to Japan.

Let’s start with the most obvious problem in the article, the hydrogen fueled torch: The usual Olympic torches use LPG (propane/butane) as a fuel, a gas mixture that can be stored as a liquid under moderate pressure at normal outdoor temperatures. This makes it easy to carry a significant amount of fuel in a light weight container. Hydrogen by contrast does not liquefy unless chilled to about -252 C. Hydrogen powered vehicles run on compressed hydrogen instead, at pressures of up to 700 bar, equivalent to half the weight of a car on each cm2 of tank surface. As you can imagine that kind of pressure calls for some fairly sturdy containers. An even bigger problem is that pure hydrogen flames are invisible because they radiate energy not as light but as UV. You could feel the heat, but you couldn’t directly see if the flame is burning or not, which makes it quite hazardous. Talk about playing with fire…

The comment about running the Olympic village on “hydrogen power” is quite misleading. It’s like saying they would run the Olympic village on battery power, without explaining where the energy to charge those batteries came from. Like batteries, hydrogen is not a primary energy source, it’s an energy carrier. Since elementary hydrogen does not exist in significant quantities on earth, it has to be produced using another energy source such as natural gas or electricity generated using coal, nuclear, wind or solar.

Though it’s possible to produce hydrogen from carbon-free energy sources such as solar electricity (splitting water through electrolysis) and then produce electricity from hydrogen again, this process is far less efficient than either consuming renewable electricity directly or via batteries. When you convert electric energy to chemical energy in hydrogen and back to electricity, about 3/4 of the energy is lost in the process. This is incredibly wasteful and far from green.

With its sponsorship of hydrogen, the Japanese government is trying to create business opportunities for industrial companies such as Kawasaki Heavy Industries, a Japanese shipbuilder (see “Kawasaki Heavy fighting for place in ‘hydrogen economy'” — Nikkei Asian Review, 2015-09-03) and for its oil and gas importers, as almost all hydrogen is currently made from imported liquefied natural gas (LNG). In the longer term, the government still has a vision of nuclear power (fission or fusion) producing the electricity needed to make hydrogen without carbon emissions. Thus the ‘hydrogen economy’ is meant to keep oil companies and electricity monopolies like TEPCO in business. The “hydrogen economy” is coal, oil and nuclear hidden under a coat of green paint.

These plans completely disregard the rapid progress being made in battery technologies which have already enabled electric cars with ranges of hundreds of km at lower costs than HFCVs and without the need for expensive new infrastructure.

Hydrogen, especially when it’s produced with carbon-intensive coal or dangerous nuclear, is not the future. Japan would be much better served by investing into a mix of wind, solar, geothermal and wave power, combined with battery storage and other technologies for matching up variable supply and demand.

See also:
Hydrogen Fuel Cell Cars Are Not The Future (2016-12-05)

Hydrogen Fuel Cell Cars Are Not The Future

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On my bicycle ride last Saturday I passed a service station near Hachioji in western Tokyo that is being set up as a hydrogen station for fuel cell cars. Japan is in the process of setting up such infrastructure to support a small fleet fuel cell vehicles such as the Toyota Mirai (its name means “future” in Japanese).

For decades, hydrogen has been touted as an alternative fuel for transport once we move beyond fossil fuels. The idea was that it can be made in essentially unlimited amounts from water using electricity from solar, wind or nuclear power (from either fission or fusion reactors). The only tailpipe emission would be water, which goes back into nature.

Unlike electric cars, which have limited range compared to fossil fuel cars, hydrogen cars can be refilled fairly quickly, like conventional cars, giving them a longer operating range. Car manufacturers have experimented with both internal combustion engines (ICE) running on hydrogen and fuel cell stacks that produce electricity to drive a traction motor. Both liquefied and compressed hydrogen has been tested for storage.

Here is a Honda fuel cell car I photographed on Yakushima in 2009:

It’s been a long road for hydrogen cars so far. Hydrogen fuel cells were already providing electricity for spacecrafts in the Apollo missions in the 1960s and 70s. With the launch of production cars and hydrogen fuel stations opening now in Japan, the US and Europe it seems the technology is finally getting ready for prime time. However, the reality is quite different.

Arguably the biggest challenge for hydrogen cars now is not the difficulty of bringing down the cost of fuel cells or improving their longevity or getting refueling infrastructure set up, but the spread of hybrid and electric cars. Thanks to laptops and mobile devices there has been a huge market for new battery technology, which attracted investment into research and development and scaled up manufacturing. Eventually reduced costs allowed this technology to cross over into the automotive industry. The battery packs of the Tesla Roadster were assembled from the same industry standard “18650” Li-ion cells that are the building blocks of laptop batteries.

Li-ion batteries have been rapidly falling in price year after year, allowing bigger battery packs to be built that improved range. A car like the Nissan Leaf that is rated for a range of 135 to 172 km (depending on the model) would cover the daily distances of most people on most days without recharging during daytime. Not only are prices falling and range is increasing, the cars can also harness the existing electricity grid for infrastructure. A charging station is a fraction of the price of a hydrogen filling station.

Here in Japan I find many charging stations in convenience store parking lots, at restaurants, in malls and at car dealerships – just about anywhere but at gasoline stations, which is where the few hydrogen stations are being installed.

After the tsunami and nuclear meltdown hit Japan in March 2011, some people here viewed electric cars and their claimed ecological benefits with suspicion: The Nissan Leaf may not have a tail pipe, but didn’t its electricity come from nuclear power stations? This criticism is not entirely justified, because electricity can be produced in many different ways, including wind, sun and geothermal. Car batteries of parked cars are actually quite a good match for the somewhat intermittent output of wind and solar, because they could act as a buffer to absorb excess generating capacity while feeding power back into the grid when demand peaks. If cars were charged mostly when load is low (for example, at night) then no new power stations or transmission lines would have to be built to accommodate them within the existing distribution network.

The dark secret of hydrogen is that, if produced from water and electricity through electrolysis, it is actually a very inefficient energy carrier. To produce the hydrogen needed to power a fuel cell car for 100 km consumes about three times as much electricity as it takes to charge the batteries of an electric car to cover the same distance. That’s mostly because there are far greater energy losses in both electrolysis and in fuel cells than there are in charging and discharging a battery. A fuel cell car actually has all of the above losses, because even fuel cells still costing about $100,000 are not powerful enough to handle peak loads, therefore a battery is still required. Think of a hydrogen fuel cell car as a regular electric car with an added fuel cell stack to recharge the battery while the car is running. This means a fuel cell car suffers the relative small charge/discharge losses of a battery-electric car on top of the much bigger losses in electrolysis and fuel cells that only a hydrogen car has.

What this 3x difference in energy efficiency means is that if we were to replace fossil-fueled cars with hydrogen-fueled cars running on renewable energy, we would have to install three times more solar panels and build three times as many wind turbines as it would take to charge the same number of electric cars. Who would pay for that and why?

Even if the power source was nuclear, we would be producing three times as much nuclear waste to refill hydrogen cars than to recharge battery-electric cars — waste that will be around for thousands of years. That makes no sense at all.

So why are hydrogen fuel cell car still being promoted then? Maybe 20-30 years ago research into hydrogen cars made sense, as insurance in case other alternatives to petroleum didn’t work out, but today the facts are clear: The hydrogen economy is nothing but a boondoggle. It is being pursued for political reasons.

Electrolysis of water is not how industrial hydrogen is being produced. The number one source for it is a process called steam reformation of natural gas (which in Japan is mostly imported as LNG). Steam reformation releases carbon dioxide and contributes to man-made global warming. By opting for hydrogen fuel cell cars over electric cars, we’re helping to keep the oil industry in business. That you find hydrogen on the forecourt of gas stations that are mostly selling gasoline and diesel now is not a coincidence. Hydrogen is not the “fuel of the future”, it’s a fossil fuel in new clothes.

Due to the inefficiency of the hydrogen production it would actually make more sense from both a cost and environmental point of view to burn the natural gas in highly efficient combined cycle power stations (gas turbines coupled with a steam turbine) feeding electricity into the grid to charge electric cars instead of producing hydrogen for fuel cell cars from natural gas.

Even if electrolysis is terribly inefficient, by maximizing demand for electricity it can provide a political fig leaf for restarting and expanding nuclear power in Japan. Both the “nuclear fuel cycle” involving Fast Breeder Reactors and the promise of nuclear fusion that is always another 30-50 years away were sold partly as a power source for a future “hydrogen economy”.

While I’m sorry that my tax money is being used to subsidize hydrogen cars, I don’t think hydrogen as a transport fuel will ever take off in the market. Electric cars came up from behind and overtook fuel cell cars. The price of batteries keeps falling rapidly year after year, driven by massive investment in research and development by three independent powerful industries: IT/mobile, automotive and the power companies.

The hydrogen dream won’t die overnight. I expect the fuel cell car project will drag on through inertia, perhaps until battery electric cars will outnumber fossil fueled cars in Japan and only then will finally be cancelled.