FAQs

How would a return to horse drawn vehicles compare with an EV on emissions?
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Well, for human power emissions, cycling generates around 8 gCO2/km if you assume the cyclist eats locally grown organic food.

If you then also assume that a horse can exert around 7.5 times the power of a human (1 hp or 750 Watts versus 100 Watts), then we would estimate that a horse (eating locally grown farm food) would emit around 55-60 gCO2/km.

This is close to what can be achieved by an electric car (on a life cycle basis), although an EV using renewable electricity would emit less CO2!

Am I right in thinking that it's all about efficiency rather than the fuel source? I believe power plants are more efficient than a car engine.
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Yes, it is certainly the case that the battery-motor combination as used by an EV is much more energy efficient than the internal combustion engine. Typically petrol and diesel engines utilise 25-30% of the fuel's energy at best.

Just for an idea of scale, on a RAC Brighton to London run, measured in mega joules (MJ) per kilometre on a tank-to-wheel basis, on average: Electric vehicles used 0.61MJ/km; hybrids used 1.16 MJ/km; and diesels used 1.74 MJ/km.

Are electric vehicle really better for the environment? I have heard that they use more energy to make them than they save in use.
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You are right to raise the issue of manufacture versus usage. Several studies have looked at these issues and broadly come to the following conclusions.

While it is the case that EV manufacture generates more emissions than the manufacture of a conventional vehicle (up to double), the benefits in use continue to outweigh the production penalty. This arises in part due to the fact that the majority (around 85%) of conventional vehicle emission occur in use, and in part due to the fact that EVs are much more energy efficient than the internal combustion engine.

Taken overall, for CO2 emissions, electric vehicles charged using average UK 'mains' electricity show a modest but important reduction in life cycle emissions of around 20% compared to an equivalent conventional vehicle. However, larger carbon reductions are likely as the UK grid continues to 'decarbonise', and if renewable or 'green tariff' electricity is used, then life cycle CO2 emissions (arising from the fuel cycle) are effectively zero.

For local pollutants, such as nitrogen oxides (NOx) and particulates (PMs), life cycle emissions associated with electric cars using average 'mains' electricity are increased. However, as these are emitted from power-stations which are well away from urban areas, their overall impact tends to be much less than when emitted from the exhausts of petrol and diesel cars. As is the case with CO2 emissions, if renewable electricity is used, then life cycle air quality impact (as measured in the main population centres) is greatly reduced.

However, it should also be stressed that it depends where the EV is used and the above figures are only relevant to the UK. A recent study by the Norwegian University of Science and Technology has made estimates of the life cycle emissions for a number of countries around the world, and draws very different conclusions depending on which country is the basis of the analysis and how the electricity is generated.

More contentious is the generation of new impacts, ones not currently associated with conventional vehicle production. While electric vehicles can provide climate change benefits, reduce noise pollution, and reduce use of fossil fuels, they may increase the potential impact on human health in areas where resources (such as lithium) are extracted for battery production. More research is required to better understand the health impacts of particular mining practices, as well as the potential of recycling as a way of reducing the need for new lithium supplies.

References

  • Preparing for a life cycle CO2 measure. Report by Ricardo on behalf of Low Carbon Vehicle Partnership, May 2011.
  • Market delivery of ultra-low carbon vehicles in the UK. Report by Ecolane on behalf of RAC Foundation, January 2011.
  • Strategies for the uptake of electric vehicles and associated infrastructure implications, ElementEnergy (for The Committee on Climate Change). Final Report, October 2009.
  • Comparative Environmental Life Cycle Assessment of Conventional and Electric Vehicles, Norwegian University of Science and Technology, 2012.
I’d like to install a charge point near my house. Is that possible? Also, are there any grants to help with installation costs?
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In February 2013, the second round of Government funding for installing EV recharging points was announced. Worth £37 million, the infrastructure grants are part of the £400 million allocated to increase the uptake of ultra-low emission vehicles in the UK.

Building on the success of the first Plugged-in Places (PiP) scheme, the latest grants support the cost of installing publicly accessible charging points as well as home-based charging units and those sited at modal interchanges.

To support owners of plug-in vehicle, the Homecharge scheme provides up to 75% (capped at £700 including VAT) of the total capital costs of the charge point plus associated installation costs. Eligible units include a single dedicated unit rated at 3 kW (Mode 2 ‘slow’, 16A, fitted with a domestic 3-pin socket) or 7 kW (Mode 3 ‘fast’, 32A, typically using a Type 2 'Mennekes 'connector). All current EVs are currently able to use either Mode 2 or Mode 3 charging units using an appropriate connecting cable.

Workplace subsidies have been offered through Travel West (The Local Sustainable Transport Fund). However, this is dependent on the terms of the local authority involved.

For more info: https://www.gov.uk/government/collections/plug-in-vehicle-chargepoint-grants.

How long does it take to charge an EV?
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The most common method of EV charging uses a standard single-phase 13 Amp AC (alternating current) supply. With an available power rating of 3 kW, ‘slow’ charging as it is sometimes known is ideally suited for overnight (off-peak) charging and a full charge typically taking 6 to 8 hours.

‘Fast’ AC charging reduces charge times to around half that of a slow charge by at least doubling the current to around 32 A (7 kW) – so that the time for a full charge is typically taking 3 to 4 hours. Higher power rates of up to 22 kW (three-phase) are also available. Most commercial and a many public on-street chargers use this technology.

While not all electric vehicles are able to accept a fast charge at 32 A, most can be connected to them (with the right connector) and will draw less than 32 A depending on their capability. Hence the charging time may be closer to 6-8 hours for these vehicles even though more current is available for others.

Faster still are ‘rapid’ chargers which supply an electric vehicle directly with either a direct current (DC) or alternating current (AC) from a dedicated charging unit using a specialised plug socket (usually CHAdeMO or CCS for DC, and Type 2 'Mennekes' for AC). Typically rated at 50 kW for DC units (400V /125A), or 43 kW for AC chargers, rapid charging an electric vehicle to 80% typically takes less than half an hour.

I’m confused about the number of charging types and worried that my EV won’t be able to connect to a particular charger.
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You are not alone in being confused! Let us try and make the technology options clearer...

The most common method of EV charging uses a standard single-phase 13 A AC (alternating current) supply. With an available power rating of 3 kW, ‘slow’ charging as it is sometimes known is ideally suited for overnight (off-peak) charging.

Nearly all electric models can be slow charged with vehicles being supplied with a charging cable with the appropriate connector which in most cases will be a standard 3-pin plug (BS 1363) at the charging point end and a ‘gun-shaped’ Type 1 (SAE J1772) or Type 2 (Mennekes) plug for connection to the vehicle.

While any 13 A socket can in principle be used, it is advisable that a qualified electrician conducts a house survey to ensure that the wiring safety supports the relatively long periods of charging.

‘Fast’ AC charging reduces charge times to around half that of a slow charge by at least doubling the current to around 32 A (7 kW). Higher power rates of up to 22 kW (three-phase) are also available. Most commercial and a many public on-street chargers use this technology.

While not all electric vehicles are able to accept a fast charge at 32 A, most can be connected to them (with the right connector) and will draw less than 32 A depending on their capability. In most cases, the connector cable used incorporates a Type 2 (Mennekes) plug (IEC 62196) at the charging point end and a ‘gun-shaped’ Type 1 (SAE J1772) or Type 2 (Mennekes) plug for connection to the vehicle.

Faster still are ‘rapid’ chargers which supply an electric vehicle directly with either a direct current (DC) or alternating current (AC) from a dedicated charging unit using a specialised plug socket (usually CHAdeMO or CCS for DC and Type 2 Mennekes for AC). Typically rated at  50 kW for DC units (400V /125A), or 43 kW for AC chargers, rapid charging an electric vehicle to 80% typically takes less than half an hour.

As with fast charging, not all electric vehicles can use a rapid charger. Examples that do include the Nissan LEAF which has a charging socket for slow and rapid charging units. Unlike slow and fast chargers, the rapid units use dedicated CHAdeMO, CCS or Type 2 (Mennekes) connector that are required to carry the very high current. At least 1,000 rapid charge points are installed in the UK with many more planned for installation in 2015-16.

Before you buy or use an EV, check the type of charging its accepts (‘slow’ also known as Mode 2, ‘fast’ also known as Mode 3, or ‘rapid’ Mode 4). Then check which of the local on-street points match your vehicle and whether you need a particular cable to connect. In most cases the charging network (such as Source West) will be able to supply a suitable connecting cable.

Also, if you are installing a home charge point, the supplier will be able to advise on the correct charger type and which options you should consider so that future EV models will also be able to use the equipment installed.

Beyond the high price of EVs, what economic benefits are available for EV owners?
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Beyond purchase, three financial incentives are also available which reduce EV running costs. These include Vehicle Excise Duty (aka ‘car tax’) which is zero-rated for BEVs and plug-in hybrids (with CO2 emissions of 100 g/km or less), zero-rated fuel tax (no fuel duty is added to electricity which also only attracts 5% VAT), and for drivers in the South East, EVs do not pay the London Congestion Charge as they are eligible under the Ultra-Low Emissions Discount scheme.

For a private driver with average annual mileage (around 10,000 miles), as compared to a typical small conventional car, fuel costs would be reduced by around £800, car tax reduced by around £100, and the ULED Congestion Charge discount could amount to as much as £2,000.

Businesses are also able to claim an Enhanced Capital Allowance (ECA) on battery electric and plug-in hybrid vehicles (with CO2 emissions of 75 g/km or less) if registered by a business soley for business use (excluding rental and short-term hire vehicles). To qualify, the vehicle must be brand new, and the purchase must be made before 31 March 2018.

Company car drivers also benefit from choosing ultra-low emission electric vehicles as zero-emission battery electric cars and plug-in hybrids with CO2 emissions up to 50 g/km attract the lowest BIK (benefit-in-kind) rate of 5%. While BIK rates for battery electric models and plug-in hybrids with CO2 emissions up to 50 g/km will increase to 7% in April 2016 and then 9% in April 2017, EVs will continue to attract the lowest BIK rate until at least 2020.

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