Climate explained: could electric car batteries feed power back into the grid?

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Alan Brent, Te Herenga Waka — Victoria University of Wellington

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Climate Explained is a collaboration between The Conversation, Stuff and the New Zealand Science Media Centre to answer your questions about climate change.

If you have a question you’d like an expert to answer, please send it to climate.change@stuff.co.nz

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Why can’t I use the battery from my electric car to export solar power to the grid when I don’t need it?

Technically it is possible. You could charge your electric vehicle (EV) with solar photovoltaic panels (or any other means), and if the EV is not used, the stored energy could be pushed back into the grid, especially during hours of peak demand for electricity when market prices are high.

This is known as vehicle-to-grid technology and is seen as the future as we move towards more electrification of transport and a smart grid.

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Read more:
New Zealand wants to build a 100% renewable electricity grid, but massive infrastructure is not the best option

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But manufacturers of electric vehicles have been reluctant, at first, to allow the bidirectional flow of power, for two reasons.

First, it could accelerate the degradation of batteries, which means they would need to be replaced more often. Second, the EV has to connect to the grid in the same way a solar photovoltaic system does, complying with standards to protect line operators and maintenance personnel working on the grid.

Such advanced bidirectional charge controllers come at an additional cost. Nevertheless, EV manufacturers such as Audi and Nissan have now taken steps to enable vehicle-to-grid connection with some of their models.

For EV models that do not have onboard inverters (to convert the DC electricity in the electric car to AC electricity we use in our homes), there are now bidirectional inverters available to connect any electric car. But the issue of battery life remains.

The continual charging and discharging through a 90% efficient converter shortens the life of the battery, and depending on brand and model, it may need replacing every five years. At more than NZ$5,000, this is a significant price tag for “energy prosumers” – people who both produce and consume energy.

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Read more:
Climate explained: the environmental footprint of electric versus fossil cars

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Economic and practical considerations

There are other considerations that are very context-specific. These relate to the additional charges for enabling the export of electricity from households, which vary between lines companies and retailers (or local authorities), as well as the buy-back rate of the electricity, which again depends on the purchaser of the electricity.

At the moment, these specific circumstances are seldom favourable to justify the additional cost of the infrastructure needed to connect an electric car to the grid.

There are also practical considerations. If the EV is used for the morning and evening commute, it is not at the home during the day to be charged with a solar system. And if it is (hopefully) not charged during peak demand hours, but mostly in off-peak hours at night, then the vehicle-to-grid route makes less sense.

It only starts to make sense if an EV is not used daily, or if EVs are available to a larger network than just one household. There are major opportunities for EVs to be used in communities with microgrids that manage their own generation and consumption, independent of the larger grid, or if large smart grid operators can manage distributed EVs remotely and more efficiently.

Investigations are ongoing to make this a more practical reality in the near future.

Alan Brent, Professor and Chair in Sustainable Energy Systems, Te Herenga Waka — Victoria University of Wellington

This article is republished from The Conversation under a Creative Commons license. Read the original article.

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New Zealand poised to introduce clean car standards and incentives to cut emissions

Australia and Russia could soon be the last remaining developed nations without fuel efficiency standards, with New Zealand proposing new rules and financial incentives to get more people driving cleaner cars.
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Robert McLachlan, Massey University

The New Zealand government has proposed new fuel standards to cut greenhouse emissions, along with consumer rebates for cleaner cars – paid for by fees on high-polluting cars.

The long-awaited proposed changes would bring New Zealand in line with most other developed countries; apart from New Zealand, Russia and Australia are the last remaining OECD nations without fuel efficiency standards.

New Zealand’s long tradition of not regulating its car market, combined with substantial indirect subsidies for private cars, makes addressing emissions from the transport sector both challenging and highly significant.

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Read more:
Four ways our cities can cut transport emissions in a hurry: avoid, shift, share and improve

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New Zealand’s second-rate car fleet

Land transport emissions – the single largest source of fossil carbon dioxide in New Zealand – grew 93% between 1990 and 2017. There are multiple causes. The population grew 44% during this period, mostly through immigration. The car ownership rate also grew rapidly, partly due to economic growth and deficiencies in public transport in the main cities. Car ownership in New Zealand is now the highest in the OECD and there are more motor vehicles than adults.

Fuel efficiency improved only slowly over this period, before stalling in recent years: at 180g CO₂/km, the emissions of newly imported vehicles in New Zealand are 50% higher than in Europe. Because of the lack of a fuel efficiency standard, importers provide less efficient versions of their bestsellers to the New Zealand market. Of the ten bestselling new vehicles, five are utes (which also benefit from a fringe benefit tax exemption, four are SUVs and one is a regular car.

In addition, half of all vehicles are imported secondhand, mostly from Japan. They are cheap, but less efficient than newer models. Emissions, and congestion, are likely to continue rising as the national vehicle fleet is increasing by 110,000 vehicles a year.

One bright spot in the present situation is the emergence of an electric vehicle segment, mostly driven by the availability of cheap second-hand Nissan Leafs from Japan and the construction of a fast-charging network by a private company. Although sales have stalled in the past year at a market share of 2%, there are now 15,000 electric vehicles in New Zealand. (Australia has around 10,000 electric vehicles.)

New Zealand’s history of fuel taxes

New Zealand does not have a strong record of taxing “bads”. The only goods subject to excise taxes are tobacco, alcohol and fuel. The fuel tax is moderate by international standards. Over the past decade, the fuel tax has been fully allocated to road construction and maintenance.

New Zealand has an emissions trading scheme. The current carbon price of NZ$25/tonne of carbon dioxide adds five cents per litre to the price of fuel. Clearly, any likely increases in the carbon price are not going to be enough to change car buying decisions. Research shows that consumers tend to focus on upfront costs, while underestimating future fuel and maintenance costs.

Despite that, a special Auckland fuel tax of 10 cents per litre that co-funds public transport investment provoked a brief but intense backlash from the public. Plans to extend the scheme to other centres were canned.

A two-pronged plan

The proposed fuel efficiency standard would require car importers to either meet it or pay a fine. The suggested standard is 150gCO₂/km in 2021, falling to 105gCO₂/km in 2025, with further falls thereafter. There are more than 3000 car importers in New Zealand, so this could prompt a major shakeup, including possible price adjustments.

The standards are similar to those proposed by the Australian Coalition government in 2016, which have not yet been taken any further. Internationally, fuel efficiency standards cover 80% of the light vehicle market.

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Read more:
Australians could have saved over $1 billion in fuel if car emissions standards were introduced 3 years ago

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But the second component of the proposal, the clean car discount, has attracted more attention. Cars emitting less than the current threshold would received a discount, initially up to NZ$1800 for an efficient petrol car, up to NZ$4800 for a hybrid and up to NZ$8000 for a battery electric car. Cars costing more than NZ$80,000 would not receive a discount.

Known as a “feebate scheme”, those rebates would be paid for by increased fees for high-polluting cars, of up to NZ$3000. The amounts are designed so that the entire scheme would be revenue neutral to the government. Modelling suggests that the proposed standard and discount combined would save motorists NZ$12,000 over the life of a vehicle.

International clean car schemes and testing

There is international experience with similar schemes, and they have been broadly effective. France has been operating a “feebate” scheme since 2008 with periodic adjustments. New Zealand’s proposed scheme is similar to the French and Swedish schemes.

But there is also room to get it wrong. Tinkering with electric vehicle incentives has led to wild sales fluctuations in the Netherlands and Denmark.

The spread between tested and real-world fuel use has widened, up from 9% in 2001 to 42%. The new Worldwide Harmonised Light Vehicle Test Procedure testing cycle, currently being adopted by Japanese and European manufacturers, is believed to be more representative of real-world fuel use, as is the test already in use in the United States.

But overall, the New Zealand proposal has been received positively by car makers and across political parties.

One possible weakness is that it is entirely based on carbon dioxide. Other pollutants, including nitrous and sulphur oxides and particulate matter (soot), that are responsible for most of the immediate health impacts of vehicle pollution and are worse in diesel than in petrol vehicles, are not targeted. Nor are the underlying subsidies to the car-based transport system, which make a transition to active and public transport more difficult.

Any decisions made now will have impacts for decades to come. Switching the fleet to electric is different from just switching to more fuel-efficient cars. It involves new charging infrastructure and some behavioural changes from the public, and these challenges (rather than simply cost) are stumbling blocks worldwide to more rapid adoption.

These arguments have persuaded many countries to bring in electric vehicle incentives beyond simply targeting carbon dioxide. Norway is a famous example, where electric vehicles avoid purchase taxes and market share is already 60%. The UK has recently exempted electric company cars from fringe benefit tax.

As the global market share of electric vehicles still stands at only 2%, eight years after they became widely available, and the number of fossil-fueled vehicles is increasing by 48 million a year, stronger action on vehicle emissions is clearly needed worldwide.

Robert McLachlan, Professor in Applied Mathematics, Massey University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Australia still lags behind in vehicle emissions testing

Emissions from real-life urban driving can be much higher than advertised.
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Zoran Ristovski, Queensland University of Technology and Nic Surawski, University of Technology Sydney

Australian cars are using 23% more fuel than advertised, according to a report from the Australian Automobile Association, which also claims that eco-friendly hybrid electric cars emit four times more greenhouse gas than the manufacturers advertise.

The report on real-world (that is, on-road) emission testing was commissioned by consultancy firm ABMARC to test 30 cars twice on Melbourne roads. The method used to measure both the emissions and the fuel consumption was a so-called Portable Emissions Measurement System (PEMS).

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Read more: The VW scandal exposes the high tech control of engine emissions

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They found that when compared to the laboratory limits, on-road vehicle NOx (a toxic gas pollutant) emissions were exceeded for 11 out of 12 diesel vehicles, and carbon monoxide (also a toxic gas) emissions were exceeded by 27% of tested petrol vehicles.

However, the key consideration here is the phrase “comparison to the laboratory limits” because on-road tests can’t directly be compared to the laboratory test limits, for several key reasons.

How are emissions from vehicles measured?

Australian Design Rules (ADR) stipulate that before introducing a new vehicle model on the market, every car or truck manufacturer in Australia has to test one new car in the laboratory.

This is done by placing the vehicle on a chassis dynamometer, connecting the exhaust to highly accurate emissions-measurement equipment, and driving the vehicle according to a strictly defined routine.

The chassis dynamometer simulates the load conditions that the vehicle would experience if it were driven on a road. In current practice, the New European Driving Cycle (NEDC) is used. This defines the speed of the vehicle and rate of acceleration for every second of the 20-minute test.

There is strict control of the testing protocol, with stipulations on how and when the gears should be changed, right down to minute details such as turning off the radio while the headlights are on. This strict control enables testers to compare the performance of different vehicles measured in different laboratories around the world.

However, these highly defined conditions have led to certain manufacturers enabling the car’s engine management system to recognise when it is being tested and to adopt and produce cleaner exhaust emissions. The most famous example of this is the recent VW scandal that affected millions of vehicles worldwide.

Even though the driving cycle has “new” in its name, NEDC was designed in the 1980s and today can be considered outdated.

Real Driving Emissions

To address these challenges, Real Driving Emissions (RDE) tests were developed. RDE tests measure the pollutants emitted by cars while driven on the road. To run a RDE test, cars are fitted with a Portable Emissions Measurement System (PEMS).

A PEMS is a complex piece of equipment that sits in the back of the car and monitors key pollutants emitted by the vehicle in real time as it is driven on the road.

These tests have proved extremely useful in highlighting some of the shortfalls of the laboratory tests. They can be run for much longer periods (several hours as compared with 15-30 minutes in the laboratory) and can give us information on long-term emission performance of the vehicles. They will not replace laboratory tests, but can provide additional information.

RDE requirements will ensure that cars deliver low emissions during on-road conditions. In 2021, Europe will become the first region in the world to introduce such complementary on-road testing for new vehicles.

RDE tests still face several unresolved challenges. The first is that the PEMS are still being developed and are not as accurate as the lab measurement equipment. The second, and more important, is the variability that one encounters while driving in real-world road conditions.

In order to compare the RDE test results with the laboratory-based standards a “conformity factor” is defined as a “not to exceed limit” that takes into account the error of measurements. This error is due to the PEMS equipment being less accurate, the variability in road conditions and driving behaviour, and thus the fact that the RDE tests will not deliver exactly the same results for each run.

A conformity factor of 1.5 would mean that the emissions measured by the PEMS in an RDE test should not exceed the standard NEDC test by more than a factor of 1.5. This is exactly the value that European Union legislators want to introduce – but not before 2021.

Australia is years behind

Australia remains years behind the European Union when it comes to vehicle emission standards.

The Euro emissions standards define the acceptable limits for exhaust emissions of new vehicles sold in the EU. Australia introduced the Euro 5 emission standards in 2016 as compared to Europe, which introduced these in 2009. At that time EU abolished the Euro 5 standard for already new ones in 2015.

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Read more: Australia’s weaker emissions standards allow car makers to ‘dump’ polluting cars

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Australia needs to upgrade to meet Euro 6 standards in order to provide effective detection of new vehicles. These include measures such as remote sensing as part of a vehicles road-worthiness assessment. This would help to ensure the maintenance status of vehicles and deliver compliance with Euro 6 RDE legislation.

What the Australian Automobile Association report highlights most of all is that the in-use vehicles (whether or not they are hybrid vehicles), many of which fall under the Euro 5 standard (or older), have almost all failed emission tests.

Until Australia updates our vehicle testing regimes to meet international standards, it will remain extremely difficult for Australians who want to buy an energy-efficient vehicle to make an informed purchasing decision.

Zoran Ristovski, Professor, Queensland University of Technology and Nic Surawski, Lecturer – Air Quality/Vehicle Emissions, University of Technology Sydney

This article was originally published on The Conversation. Read the original article.

Netherlands: Building the World’s Largest Electric Vehicle Charging Network

The link below is to an article reporting on the Netherlands’ plans to build the world’s largest network of electric vehicle charging stations.

For more visit:
http://inhabitat.com/abb-to-build-worlds-largest-network-of-electric-vehicle-fast-charging-stations-in-the-netherlands/

Holiday Update

My latest holiday plan has gone flop – the back packing holiday is a no-goer. Reason? It would seem from all reports that the Tops to Myalls Heritage Trail has been abandoned, with parts of the route now so overgrown as to be unrecognizable. I have been told of walkers in recent times having to back track a fair distance when the way ahead was no longer able to be walked. So as disappointing as it is I have abandoned the trail myself and will now do something else.

With time running out for a settled option, I have decided to fall back on an earlier idea and that is to visit the Cathedral Rocks National Park and possibly do some further walks at the Dorrigo National Park. I have booked a vehicle (car rental) for the trip so things are fairly settled now as far as the destination is concerned. I am now going to put some meat on the bones of my idea and draw up an itinerary, Google Map, etc. So some real detail of what I plan to do will be coming over the next few weeks.

This isn’t going to be an expensive holiday or a long one, but is mean’t to be a simple time-out break and one that will allow me to plan some much bigger holidays for later in the year and into the coming year also.

AUSTRALIA: TRAGEDY IN THE OUTBACK – Man Found Dead in the Kimberley

A man thought to be from Queensland has been found dead in the Australian outback. The body was found in Western Australia’s Kimberley region, in the far north of the state on the Meda cattle station, about 40km west of Derby.

Near the body was the man’s desperate plea for assistance with the word ‘help’ written in the dirt. He had constructed a shelter and his water bottle was empty. No vehicle has yet been found.

The man was some 15km from the Meda cattle station homestead on the 1.25 million acre property.

The temperatures in this region had reached 40C last week. The man is thought to have died a few days ago.

CROCODILE ATTACK NEAR COOKTOWN IN QUEENSLAND

A terrible tragedy is unfolding near Cooktown in Queensland, Australia. An Australian fisherman has probably been taken by a 6 metre crocodile on the Endeavour River while checking crab traps on foot. Arthur Booker, 62, from the town of Logan, south of Brisbane has not been seen since about 8.30am Tuesday morning.

The man and his wife were on a two-day holiday at the Endeavour River Escape campsite near Cooktown, north of Cairns in Queensland. Mr Booker had already packed his boat on the top of his 4WD vehicle in preparation to leave.

A local crocodile known as Charlie is the alleged culprit of Arthur Booker’s disappearance according to local Terry Rayner. However, Queensland Parks and Wildlife Service regional manager James Newman has said that there are other large crocodiles in the area.

Police are searching for the man but all that has been found is the man’s watch and footwear. The search will continue tomorrow.

BELOW: Footage of the Endeavour River, scene of the attack and the search for the victim.