Tokyo in a power crunch

On March 22, 2022 the Tokyo Electric Power Corporation (Tepco) warned electricity consumers in east Japan about the risk of rolling blackouts from a tight supply situation. The recent M7.3 quake near Sendai had knocked several of Tepco’s thermal power plants offline, which left the company in a difficult situation when a cold spell with snow flakes hit the region of the capital. Demand at times exceeded generation capacity and only the availability of pumped hydro storage saved the day before measures to curb demand such as turning down heating and switching off lights averted an outage.

No doubt this experience will increase pressure to restart more nuclear power stations that have been shuttered since the tsunami and nuclear meltdowns in Fukushima in March 2011. Before the nuclear disaster about 30% of Japanese generating capacity were nuclear; now only about 10% comes from restarted nuclear reactors. The current high prices of natural gas will further enhance the attraction of nuclear, at least in the eyes of anyone whose financial interests are tied to the balance sheet of the utility companies, such as their individual and institutional shareholders.

However, that is not the whole story.

While eastern Japan was in a power crunch, western Japan has ample spare capacity, as did Hokkaido. Why could this power not be used in Tokyo? You would have thought Japan would have learnt its lesson from the 3/11 disaster in 2011 and addressed it in the decade since then, but you would be wrong: Japanese electricity markets are still split between a handful of regional near-monopolies with minimal interchange capacities between them. For example, the Hokkaido grid has a generating capacity of 7.5 GW but only 0.6 GW of interchange capacity with Honshu (8% of the total). Tepco supplies up to 47 GW to customers in its area but can only exchange up to 1.2 GW with major utilities in the west of Japan. This leaves little margin when earthquakes or weather events with a regional impact hit supplies.

By contrast, China has built huge high voltage direct current (HVDC) transmission lines between the industrialized coastal cities on one side and hydroelectric power stations near the Tibetan plateau and solar and wind farms in the arid north on the other. Many of these lines are longer than the distance from Tokyo to Hokkaido, let alone Tokyo to Kansai. The Chinese government understands that if it wants to wean itself from the dependence of dirty coal or imported oil and gas then it will need to vastly increase power transfer capacity from the interior of the country where renewables are available to the densely populated urban areas near the coast lines.

Japan is actually in a similar situation. The elephant in the room that nobody wants to talk about is offshore wind. While European countries and the US are building up tens of Gigawatts of offshore wind power capacity, Japan has very little installed capacity, particularly offshore. The entire conversations seems to be about nuclear vs. solar vs. gas vs. coal, leaving out one of the most promising renewable energy sources available to Japan. So far the regulatory hurdles for erecting and connecting wind turbines in Japan have been high and that has left wind as an also ran compared to much more widely deployed solar. However, solar does not provide power at all hours. Wind would complement it.

Much of the European wind power capacity is installed offshore where wind speeds tend to be high and more consistent than onshore. This is where the largest and most economical turbine models tend to be used. By contrast, almost 99% of Japan’s wind power capacity is still onshore. A cumulative total of only 51.6 MW of offshore wind capacity was installed at the end of 2021 while total installed wind power capacity was 4.6 GW. Meanwhile the UK had 24.7 GW of wind power capacity, Spain 27.1 GW and Germany 62.2 GW. China is in a league of its own with 282 GW, more than all of Europe combined. Japan’s installed wind power base is less than that of small European countries such as Belgium (4.7 GW) that have relatively short coast lines and tiny EEZs: Japan’s EEZ of 4,479,388 km2 is over 1000 times larger than Belgium’s at 3,447 km2!

Japan is really only starting to build up offshore wind capacity, with projects off the coasts of Akita, Chiba and Nagasaki getting under way in the last two years. By 2030 its goal is for 10 GW of offshore capacity either installed or under construction which is still tiny compared to the already installed base of Germany, Spain or the UK.

Unlike fossil fuel or nuclear power stations, wind turbines are not location independent. They will be installed where wind conditions are favourable, where the sea is not too deep and connections to the coastal grid are cost-effective. To make the most of the wind conditions, the grid will need to be greatly expanded to allow large amounts of power to be transferred from regions with plenty of wind to regions with many consumers. This will be quite different from the current model where utility companies try to generate all the power they need within their own region, which is why there is only limited interchange capacity to help out if one company loses a large part of its generating capacity as happened in the recent quake or after 3/11.

Japan needs to start building high capacity long distance HVDC power lines like China has in order to enable a transition to zero carbon electricity. The fragmented power markets dominated by local utility companies are an obstacle to this transition as the interests of the regional companies seeking profits from existing investments in their area are not aligned with the interests of the consumers who want reliable green energy regardless of where it comes from.

Japan quickly needs to remove regulatory obstacles to expanding wind power and then invest to build a HVDC backbone to connect renewable power generation with consumers.

Hokkaido wind power for Japanese energy

Nikkei reports (“Japan pushes for undersea cables to solve wind power puzzle”, 2022-01-02) that the government is allocating 5 billion yen (about US$43 million) in its supplementary budged for a feasibility study for a 4 GW high voltage direct current (HVDC) link between the power grids of the northern island of Hokkaido and the main island of Honshu, where most of Japan’s population lives. This would be by far the biggest HVDC link ever built in Japan. The Japanese government wants to generate 45 GW of power from offshore wind in 2040, up to about a third of which (14.65 GW) is to be produced in Hokkaido. The development plan lists several promising offshore areas along the southwest coast of Hokkaido.

For this power to be available to consumers outside the northern prefecture, it would need to be exported via a HVDC link. This is the preferred technology for shifting large amounts of power over long distances, especially between AC grids not synchronized with each others or operating on different frequencies. Since 2019 there have been two 300 MW HVDC links between the two islands. Their combined capacity is to be doubled to 1.2 GW by 2028.

Japan has relatively little capacity for transferring power between its regional grids. This is because its grids used to be operated by regional monopolies that had little incentive to ever import or export power. This lack of interconnect capacity became a major problem following the power shortage after the 2011 Tohoku earthquake and tsunami when less affected areas could not help out the most affected region. There is a conflict of interest between the local utility companies and the country as a whole. Tepco owns a lot of nuclear power stations, expensive infrastructure with huge sunk costs. It would rather generate power from these plants than pay another supplier from outside its area for renewable energy. However, many of these power stations have yet to be restarted since their shutdown following the Fukushima meltdowns. By restricting how much power can be imported from other grids, Tepco can put pressure on regulators to allow it to restart more reactors to ensure a stable supply of power. On the other hand, expanding interconnect capacity would ease the pressure. Which side will the Japanese government take?

A related issue is the variable output of renewable power sources. Long distance transmission will make it easier to compensate for local weather patterns by shifting power between different regions, which allows a larger share of renewable energy to become part of the mix without having to resort to either energy storage or peaker plants (e.g. gas turbines to cover peak loads). That again means Tepco loses leverage to maintain coal and other fossil fuel powered generating capacity as insurance against shortfalls of renewable energy.

China, one of Japan’s main economic rivals in the world, has pursued a completely different course. Over the past decade it has aggressively expanded long distance HVDC links to stabilize its grid. Japan operates a single HVDC link of at least 1 GW, a 1.4 GW link between Honshu and Shikoku that started operating in 2000. All other links are only in the several 100 MW range and most of those are not long distance lines but back-to-back local interconnects, for example between the 50 Hz grid of eastern Japan and the 60 Hz grid of western Japan near Nagoya. By contrast, China has built over 20 HVDC links over 1 GW, mostly with a capacity of 3 GW or more. Many of the biggest projects cover distances of 1,000 to 2,000 km. This allows China to supply it coastal megacities with hydroelectric power from its southeastern mountains or from other power sources from its arid central parts. China is the world leader in wind power. Its windiest parts are along its border to Mongolia and on the Tibetan plateau. Large scale HVDC is key to China’s energy policy for the 21st century.

An alternative to shifting power long distance is to use it to locally generate hydrogen from water (“green hydrogen”) and feed it into pipelines or use it to make ammonia. This makes some sense for applications that already use hydrogen, such as the fertilizer industry or for carbon free alternatives to existing technology, such as direct reduction of iron ore for steel making without using coking coal. However, it makes little sense to use green hydrogen for power generation: if you convert electricity to hydrogen which you then use to generate electricity, more than 70 percent of energy is lost in the process while less than 30 percent remains. By contrast, batteries are 90 percent efficient. Therefore, if excess wind or solar power is used to produce hydrogen, that resource should best be used by industries that directly consume hydrogen, until all fossil fuel currently used for such purposes has been replaced.

If Hokkaido had a surplus of hydrogen from wind power, it would make more sense to have it consumed by steel works and fertilizer plants built in the prefecture rather than sending it through a pipeline to Honshu.

Although green hydrogen or ammonia can be used as fuel in thermal power plants in place of coal or LNG, it would be a terribly wasteful use. Because of the huge conversion losses, we would need three times more wind or solar power to end up with the same amount of usable electricity than if we used grid-scale battery storage to absorb any surplus and make it available when needed. This advantage makes grid-scale battery storage a strategic technology.

Most existing Li-ion batteries depend on relatively scarce resources such as cobalt, nickel and lithium. Lithium-iron-phosphate (LFP) batteries only require lithium and widely available materials, while sodium ion batteries use only readily available raw materials. Japan will need to invest in high capacity long distance HVDC links as well as in battery storage to speed up its transition to a carbon neutral economy.

The TerraPower Natrium Reactor – a Quick Review

TerraPower, a company funded by billionaire Bill Gates, has teamed up with several partners to build a demonstration nuclear power station in Wyoming by the end of the decade. Several sites are under consideration. The plan is to re-use the grid connection of a former thermal coal power plant, of which Wyoming has many.

The Natrium reactor developed by TerraPower in cooperation with GE Hitachi Nuclear Energy is quite a departure from the design of the light water reactors (LWRs) that produce the bulk of nuclear power worldwide today. For one, its output is highly variable because it incorporates gigawatthour (GWh) energy storage using tanks of molten salt. The design is quite innovative, which creates both upsides and challenges.

After reviewing the company’s website and watching a webinar, I am quite impressed but also concerned. The reactor will still run on uranium and will produce radioactive fission products that will need to be contained and stored safely for thousands of years. This is still a largely unsolved problem. Countries that have been generating power from nuclear fuels are today sitting on thousands of tons of waste kept in intermediate storage, still without a proven long term storage solution. Eight decades since the start of the “atomic age” with the Manhattan Project that gave us nuclear reactors and atomic bombs we are only now seeing the first permanent storage site being used in Finland. Some consider this the Achilles heel of the nuclear industry. Proponents of nuclear power will argue that, given we already have existing waste, this is a problem we will need to address anyway and that the volume of highly active nuclear waste will remain relatively compact. Nevertheless, there is a lot that can go wrong there, especially if the volume keeps increasing.

What most excited me about the reactor concept was its incorporation of the heat store using molten salt tanks, which it borrowed from concentrated solar power (CSP). Everything from the molten salt tank to the grid connection is basically the same as in this type of solar power plant. The major difference is that the heat source is not solar power focused onto a tower by thousands of mirrors but an underground nuclear reactor. This means the designers could use existing technology developed to maturity over the last 2-3 decades for use in solar projects in Nevada, Australia, Morocco and other locations.

This part of the plant is conventional technology that will not be subject to the same regulatory oversight as the nuclear portion, making it easier and cheaper to build. At the same time, the nuclear portion of the plant is much smaller and simpler, requiring a lot less concrete and steel than in a LWR per MW of output capacity.

By incorporating the heat storage, the electrical output of the power station can be varied considerably – the TerraPower presentation showed a range of about 240 to 500 MWe, with 345 MWe available continually without charging or discharging the heat store. Output that varies by 100 percent roughly covers the demand swing between day and night in many power markets. If combined with solar and wind, the stored heat can be used to smooth out fluctuations in power output from those natural energy sources. Heat from the power station may also have applications for desalination, industrial processes and residential heating.

Conventional nuclear power stations such as PWRs or BWRs can not vary their output very much. They basically can only run at 100 percent load or be switched off. Once shut down, bringing them back up again takes a very long time. That makes them suitable only for base load but not for demand peaks such as in the afternoon or evening. For that they would have to be combined with energy storage such as pumped hydro, opportunities for which are limited by geography. Due to the literally built-in output flexibility of the salt storage system, a zero carbon grid could theoretically incorporate a lot more Natrium output capacity than would be possible with existing LWRs. From an economic point, it means the operators in a competitive electricity market with bidding for supplies can sell more power at lucrative peak prices instead of having to try to find buyers at night when demand and prices are low.

So what’s the catch? The nuclear reactor itself is a sodium-cooled fast reactor (SFR), basically a Fast Breeder Reactor (FBR) without the breeding: Except for the absence of a breeding blanket made of depleted uranium that slowly turns into plutonium, the technology is very similar. Perhaps you remember the Monju reactor in Fukui, Japan that was shut down after a major accident in 1995. The operators attempted to hide the extent of a coolant leak and fire, which led to a 15-year shutdown. After a second accident in 2010 the reactor was eventually decommissioned. In 1966 the prototype Fermi 1 FBR in Monroe, Michigan suffered a partial meltdown. It was permanently shut down in 1972. Several other sodium-cooled fast reactors have been built around the world, such as the French Superphénix, the Prototype Fast Reactor in Dounreay, Scotland and the SNR-300 in Kalkar, Germany. All of the above have since been shut down due to high costs or troubles or, like the one in Kalkar, were never even started up.

While sodium has a high temperature range between melting and boiling point and is a good heat conductor, it also reacts violently with water and oxygen. Naturally, you can not put out a sodium fire with water. Normally the top of the reactor vessel is filled with an inert gas such as argon to prevent sodium fires but it needs to be opened for loading and unloading fuel, during which time the sodium has to remain heated above its melting point. You do not want to start a fire then.

If an LWR overheats, steam bubbles will form that reduce the criticality, interrupting the chain reaction. By contrast, control of the chain reaction in SFRs depends 100 percent on positioning of the control rods.

While the cooling pipes will not have to withstand high steam pressures as in a BWR, they will be subject to thermal stress: The coolant temperature in an SFR is much higher, around 550 deg C (1020 F) which is basically red-hot and hot enough to melt some aluminium alloys (and of course salt, for the heat storage). When SolarReserve decided to build a molten salt CSP solar power station in Nevada, it turned to Rocketdyne to make some of the metal parts, because of their metallurgical expertise in rocket engine nozzles that are also exposed to high temperatures.

There are other viable solutions for base load in a zero carbon grid, such as geothermal power, utility scale battery storage, thermal storage using rock heated electrically with surplus wind and solar or green hydrogen powering fuel cells or gas turbines. Costs for wind, solar and battery storage have been falling rapidly for years. Once renewables are cheap enough, you can partially address issues of intermittent output by overbuilding capacity and simply idling some of it when not needed. Or you can use spare output when supply exceeds demand to produce hydrogen, for making ammonia and for use by the steel industry.

Some of these solutions depend more on geography than the Natrium reactor, which can be installed on any continent and provide power at time of day and in any season. However, it would definitely need to be safe and reliable. Ultimately, this new technology will first have to prove itself.

Releasing Tritium-tainted Water from Fukushima 1

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

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.

Olympic Hydrogen Hype

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

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.

Tepco drowning in radioactive water

A recent leak of 300 tons of highly radioactive water at Fukushima No. 1 has highlighted the long term problems that Tokyo Electric Power Co. (Tepco) is facing in its struggle to manage the crisis at the wrecked nuclear power station (see Japan Times, 2013-08-21). One massive steel tank had been leaking as much as 10 tons of water a day for a month before the leak was noticed. The water level in the tank dropped by 3 m before anyone noticed. It is not clear yet how the water is escaping.

The water in the tank has been used for cooling the melted reactor cores. Consequently it is highly radioactive from strontium, cesium and tritium. At a distance of 50 cm, as much as 100 millisieverts per hour (mSv/h) were measured. That means a nuclear worker there would absorb as much radiation in one hour as is legally permitted over a total of 5 years.

You might think that with a witches’ brew like that on its hands, Tepco would take every possible precaution to prevent leaks and to monitor fluid levels. Tepco uses both welded steel tanks and temporary tanks for storing contaminated water at Fukushima No. 1. Welded tanks are supposed to be stronger and more leak proof, whereas temporary tanks can be bolted together quickly from sheet metal and plastic. About one third of the over 1000 tanks at Fukushima No. 1 are temporary tanks, including the one that recently leaked. Tanks of this type have been used at the site since December 2011 and they are supposed to last five years before needing repair or replacement. So far 4 of these tanks have leaked, yet Tepco is planning to install even more temporary tanks for storing water. I guess they must be cheaper.

I am curious why the leaks were not detected sooner. Are there no monitoring devices installed that can automatically report water levels?

Tepco is planning to treat the water in the tanks with its ALPS filtering system, which can remove radioactive cesium and strontium from the water, but not tritium. It was meant to start operating this month, but after problems it is now expected to not resume operation until December.

Even after treatment, Tepco will have a water problem. Any water pumped from the turbine halls that has been in contact with the reactor basements has elevated levels of radioactive tritium. No chemical removal system exists for tritium, as it’s an isotope of hydrogen, one of the two elements that make up water. Tepco can not simply evaporate water from those tanks to reduce volume and concentrate contaminants into a smaller volume, as the tritium would be released with water vapour and come down as rain again elsewhere. So what is it going to do? Release it into the atmosphere slowly? Dilute it with sea water? Or store hundreds of thousands of tons of water for hundreds of years? Neither alternative seems very appealing.

Japan without nuclear power

Since last weekend, Japan is without a single nuclear power station feeding power into the grid, the first time in 42 years. All 50 nuclear power stations are currently off-line (this count does not include the 4 wrecked reactors in Fukushima I, which are no longer officially counted — it used to be 54 nuclear power stations).

Some of these power stations were shut down because of problems after the March 11, 2011 earthquake and tsunami. Others were taken offline one by one for routine inspections and maintenance but have not been started up again, which would only happen with the consent of nearby local governments. That consent has not been forthcoming.

Electrical utilities and the government are raising concerns about a power shortage when the summer heat sets in, which usually results in peak usage for air conditioners. Critics of nuclear power see an opportunity for a quick exit from nuclear power. Others are concerned that if the government rushes to bring power stations back online before the summer without safety upgrades and a change in the regulatory regime, a unique chance to prevent the next nuclear disaster will be squandered. If upgrades and reforms don’t happen when the memory of Fukushima is still relatively fresh, what’s the chance of it happening a few years down the road?

The utility companies are facing high costs from buying more fossil fuels for gas and oil fired thermal power stations to cover the demand; restarting the nuclear power stations would keep those costs in check. But that is only part of the reason they are keen on a restart. The sooner they can return to the pre-Fukushima state of power generation, the less leverage governments and the public have for making them accept new rules, such as retrofitting filters for emergency venting systems or a permanent shutdown of the oldest and seismically most vulnerable stations. Because of this it’s in the interest of the utilities to paint as bleak a picture of the situation as possible. Japan would be smart to proceed cautiously and not miss a unique chance to fix the problems that are the root cause of the Fukushima disaster and of disasters still waiting to happen.

Fukushima “cold shutdown” announcement up to 25 years too soon

The Japanese government has announced that the wrecked Fukushima Daiichi power station has reached a “cold shutdown”. The BBC quotes Prime Minister Noda:

“The nuclear reactors have reached a state of cold shutdown and therefore we can now confirm that we have come to the end of the accident phase of the actual reactors.”

It is meaningless to still use the term “cold shutdown” for a reactor in which the fuel rods and containment vessel have lost their integrity. It’s like saying the bleeding has been stopped in an injured patient who had actually bled to death.

The normal definition of “cold shutdown” is when, after the chain reaction has been stopped, decay heat inside the fuel rods has been reduced enough that the cooling water temperature finally drops below 100 C. This means the cooling water no longer boils at atmospheric pressure, making it possible to open the pressure vessel cap and remove the fuel rods from the reactor core into the spent fuel pool. After that the reactor core no longer needs to be cooled.

Only units 4, 5 and 6 have reached a genuine cold shutdown. Unit 4 had been shut down for repairs in 2010 and did not contain any fuel at the time of the accident. In units 5 and 6 a single emergency diesel survived the tsunami and prevented a meltdown there.

In units 1, 2 and 3 of Fukushima Daiichi the fuel melted, dropped to the bottom of the reactor pressure vessel and penetrated it. The melted rods then dripped down onto the concrete floor of the containment vessel and are assumed to have partly melted into the concrete up to an unknown depth.

While in a regular cold shutdown fuel can be unloaded within weeks, the Japanese government estimates it may take as much as 25 years before all fuel will have been removed. The technology to remove fuel in the state it’s in now does not even exist yet and will have to be developed from scratch. Even the most optimistic schedule puts it at 5 years, during which time the reactors will have to be cooled 24 hours a day, with no new earthquakes damaging them or knocking out cooling again, no major corrosion problems, no clogged water pipes, etc.

In my opinion, the announcement of a “cold shutdown” at Fukushima Daiichi is greatly exaggerated and was made mainly for political purposes. More than anything, it is meant to provide political cover for restarting other idled nuclear power stations during the coming year.