WINTER EV SERIES PART 3 | Hokkaido’s electricity carbon efficiency deep-dive

Posted on Jan 28, 2021

Posted on Jan 28, 2021

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In Part 3 of our Winter Electric Vehicle Series, we dig into three Hokkaido electric supply scenarios and their impact on electric vehicle emissions here in northern Japan. The good news is that Hokkaido's currently dirty power grid is getting cleaner, slowly. If current trends continue, Hokkaido's sole electricity producer could almost halve their emissions within a decade. This is a boon for the potential of electric vehicles here in Hokkaido. Even better still, switching residential electricity providers to a net carbon-neutral plan could slash your EV emissions by 40% or more.

A) THE OPTIMISTIC SCENARIO: Hokkaido Electric Power Company cuts emissions 40% by 2030

Let’s start with a best-case scenario: Hokkaido Electric Power Company (HEPCO, or Hokuden) cuts its per-kWh CO2 emissions by 40% over the next decade, as they’ve stated as a goal; HEPCO has stated their 2030 goal for CO2 emissions is 370g-CO2/kWh (HEPCO, 2019, p. 43)*.

We’re cautiously optimistic that this might be achievable. Despite the fact the last 8 years have seen very little improvement in HEPCO’s CO2 emissions (see Figure 1; HEPCO, 2019), the last few years have seen a huge increase in the amount of solar and wind making up HEPCO’s electricity mix (Figure 2). 

This is good news for electric vehicles in Hokkaido in the long term.

*This goal could, of course, be achieved overnight if the Tomari Nuclear Power Plant was re-started (a rather politically charged issue), or largely untapped geothermal resources were put to good use (also a rather politically charged issue).

Key Points

If the Hokkaido Electric Power Company (HEPCO) sticks to its 2030 goal of 38% decarbonization, Hokkaido residents who charge a 62kWh Nissan Leaf on a net zero carbon residential power plan can expect at least 40% less emissions than a similar sized hybrid. These combined decarbonization efforts by both HEPCO and consumers is the only way one can justify the use of high capacity, high performance, long range EVs, if one’s focus is on doing their part for the climate. 

Carbon-efficiency of a 62kWh Nissan Leaf under the “Optimistic Scenario”

Under this optimistic scenario, a Nissan Leaf is a little bit more carbon-efficient than a similar-sized hybrid. 

Using the Luxembourg Institute of Science and Technology comparison tool, if HEPCO manages to hit their 2030 goal of 370g-CO2/kWh (a reduction of 38%), then the Nissan Leaf averages out at 145g CO₂ eq./km over its lifetime, compared to a similar sized Toyota C-HR Hybrid at 171g CO₂ eq./km (source | parameters). That’s a 15% reduction in emissions for the Leaf.

You’d still have to drive the Nissan Leaf almost 150,000km before it’s cleaner than the Toyota though.

Top = Toyota C-HR Hybrid | Bottom = Nissan Leaf

Yellow line = Toyota C-HR Hybrid | Blue line = Nissan Leaf

B) THE ACT-NOW SCENARIO: Consumers switching to a zero-carbon residential power plan

Let’s be honest: Even if HEPCO drastically reduces their emissions by 2030, a 26g/km (15%) lifecycle difference in CO2 emissions just doesn’t seem worth the extra hassle of an electric car here in Hokkaido. In 2021, electric car range is still limited, charging is slow, and options for EV purchase are laughably limited here in Hokkaido. The second hand EV market here is made up of either $25,000 second-generation Leafs, or $80,000 Teslas.

Therefore, not many rational outdoors-people in Hokkaido will turn to EV ownership based on emissions alone, if only relying on HEPCO’s efforts.

However, there is a way that Hokkaido residents can act now. There are a number of alternative electricity providers that offer low- or no-carbon residential electricity plans in Japan. For the majority of users, these plans are no more expensive (and usually cheaper) than HEPCO’s offerings.* We’re currently on Shizen Denryoku‘s SE100 plan, offering net zero CO2 emissions. Another option would be to invest in residential solar.

Make no mistake: our electricity is still coming from HEPCO’s fossil fuel power stations. But Shizen Denryoku offsets this with carbon credits from renewable sources. It’s not an ideal solution, but arguably better than the alternative.

Therefore, if we owned a Nissan Leaf, we could drastically cut the amount of ‘raw dirty’ electricity the car runs on. Yes, we would need to use ‘dirty’ public charger electricity every now and then, but this could possibly be in the minority.

Take for example our most recent weekend with a 62kWh rented Nissan LeafWe travelled a total of 325km. Let’s say we left home on a full charge on Saturday morning, charged using our ‘clean’ carbon-offset residential power plan. Let’s say due to the -25°C cold and extra drag of skis strapped to the roof, we can only do 200km on the 100% (56kWh useable) ‘clean’ charge from home. We stop in at a Seicomart convenience store and use their 30kW charger for 30 minutes along the way to our destination, giving us time for a toilet stop, lunch purchase stop, and rest. Doing so adds an extra 15kWh (63km) of ‘dirty’ charge to the car. 

At the end of the day, we stay out overnight in a cheap hotel that offers 200V 3kW charging. Overnight, this gives us an extra 30kWh (about 110km) of ‘dirty’ charge. This overnight charge is enough to get us to our destination for the day and back home, where we arrive back home with about 50km (15kWh) range still remaining.

Splitting the remaining 15kWh between ‘clean’ and ‘dirty’ sources, a rough back-of-the-envelope calculation gives us 49kWh of ‘clean’ electricity and 38kWh of ‘dirty’ electricity used for the weekend. That’s a weekend trip done on roughly 56% ‘clean’ electricity.

Using the Luxembourg Institute of Science and Technology comparison tool again, I’ve set the electricity mix CO2 emissions to 56% of HEPCO’s current emissions. 601g x 56% = 336g. I’ve again set the decarbonization of HEPCO’s power at 38% reduction over the next decade (source | parameters).

From an emissions standpoint, this makes for a much more compelling case for owning an electric vehicle in Hokkaido. Average lifecycle greenhouse gas emissions for the Leaf is 104 g CO₂ eq./km versus 171 g CO₂ eq./km for the Toyota C-HR Hybrid.

*As luck would have it, as of January 2021, Japan’s open electricity market (JEPX) is experiencing one of the country’s most severe kWh spot price increases in recent history (see a graph here). I can tell you that our monthly bills with Shizen Denryoku (which bids on the open market for electricity) is not pretty right now, even with their 30,000yen per month emergency discounts to soften the blow.

Top = Toyota C-HR Hybrid | Bottom = Nissan Leaf

Yellow line = Toyota C-HR Hybrid | Blue line = Nissan Leaf

C) THE STATUS-QUO (DOOMSDAY) SCENARIO: Hokkaido electricity supply emissions remain at 660g-CO2/kWh forever

This overview wouldn’t be complete without a doomsday-style pessimism FTW simulation. Since Hokkaido turned off the three nuclear reactors at the Tomari Nuclear Power Plant in western Hokkaido in 2011 (precautionary due to the earthquakes, due to public pressure since then), HEPCO’s CO2 emissions rocketed from 340g-CO2/kWh to an average of 660g/kWh over the last 8 years. This equates to Hokkaido, in 2021, having some of the dirtiest electricity in the developed (and undeveloped) world. 

If HEPCO abandoned its 2030 goal of 370g/kWh, what would that mean for the carbon efficiency of electric cars in Hokkaido?

Again using the Luxembourg Institute of Science and Technology comparison tool , I’ve set the electricity mix CO2 emissions to HEPCO’s 8-year average of 660g/kWh (source | parameters). 

This is not the future anyone should wish for. From an emissions standpoint, at this point you’d only own an electric vehicle for the pure performance of it. Which would be a noble reason – even the Nissan Leaf is a beast off the mark. But if ‘nice for the environment’ is your modus operandi, an electric vehicle does not make sense in a Hokkaido without a cleaner-energy future.

Average lifecycle greenhouse gas emissions for the Leaf in this scenario is 184 g CO₂ eq./km versus 171 g CO₂ eq./km for the Toyota C-HR Hybrid.

Top = Toyota C-HR Hybrid | Bottom = Nissan Leaf

Yellow line = Toyota C-HR Hybrid | Blue line = Nissan Leaf

WRAPPING UP: Electric cars can be a carbon-efficient option in Hokkaido

In conclusion, from a lifecycle emissions perspective electric cars can be a ‘not bad for the environment’ option for drivers here in Hokkaido, northern Japan. As of 2021, the Hokkaido mains electricity supply is some of the dirtiest in the developed world. But, Hokkaido’s electricity provider has set a goal to almost halve emissions over the next decade. This, coupled with carbon offset power plans available to residential users, can translate into at least a 40% reduction in emissions by driving an EV rather than a similar-sized hybrid.

It’s really important to stress that the figures in this post are very conservative. Some might say overly punishing on electric vehicles. Indeed, suggesting a 30% drop in efficiency on the Leaf in winter is quite extreme. However, I believe in showing the absolute worst an EV can do, because right now in 2021, that appears to be actually very good, practical, and useable.

We’ll be doing more tests and reviews of electric cars in the coming months, so keep tuned.

In the mean time, we’ll mostly be out skiing.

Comments | Queries | Discussion

2 thoughts on “WINTER EV SERIES PART 3 | Hokkaido’s electricity carbon efficiency deep-dive”

  1. Just read all three of these posts on EVs in Hokkaido. I must admit it was good to get an idea of the situation on the ground, I had no idea that electricity in Hokkaido was so dirty right now. It was good to see the big increases in solar and wind, but the way the whole country’s electricity grid has been managed since 2016 seems to have made it into a bit of a basket-case. The local monopolies charging outrageous prices to the smaller startup companies and refusing to accept local small lot renewable electricity onto their grids because they’re “competing” with them. If there was ever a case for local governmental control of the power grids this is it in my opinion. Then at least you could get some real coordinated policy on renewable energy and even EV charging infrastructure rather than this higgledy-piggledy nonsense.

    Nissan’s new EV the Ariya (?) looks a good bet for outdoor Hokkaido life. It’s 4WD, roomier and goes further. If half of the other domestic car-makers showed interest in EVs that’d be something, the buying options aren’t good even here in Tokyo. Toyota seems determined to push it’s hydrogen fuel cell idea (which needs clean energy infrastructure to make, store and transport the hydrogen anyway) and everyone else (including the government as per) is watching on the sidelines to see how things go. Everything just seems to be moving so slowly, it’s very frustrating.

    Thanks for the great article! I hope that Hokkaido does keep getting cleaner energy and we can protect the beauty of nature there and all over Japan.

    1. Thanks Chris. As far as Hokkaido goes, the grid would be about 50% cleaner in only a few months if only the Tomari nuclear power plant was put back online. If indeed we are in a climate emergency, then some of us here at Hokkaido Wilds see that as a very feasible and important interim measure as Hokuden works to clean up other parts of the grid. Alas, such a view seems not too popular. As for the Ariya, we’ve certainly got our eyes on it! It’d be a great option. Word on the street – i.e., we talked to a dealership – is that it’s unlikely we’ll see the 4WD long range version this year. More likely that the versions will be drip-fed to the market starting in summer. It’s a pity the Hyundai Kona isn’t available in Japan – so close, yet so far!

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WINTER EV SERIES PART 3 | Hokkaido’s electricity carbon efficiency deep-dive Difficulty Rating





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