Charging station

This article covers electrical recharging. For pneumatic recharging, see compressed air vehicle.

Nissan Leaf charging from an Andromeda Power ORCA mobile charger in Anaheim, California.

Nissan Leaf recharging from a NRG Energy eVgo station in Houston, Texas

Public charging stations in San Francisco 2009

Brammo Empulse electric motorcycle at an AeroVironment charging station

An electric vehicle charging station, also called EV charging station, electric recharging point, charging point and EVSE (Electric Vehicle Supply Equipment), is an element in an infrastructure that supplies electric energy for the recharging of plug-in electric vehicles, including all-electric cars, neighborhood electric vehicles and plug-in hybrids.

As plug-in hybrid electric vehicles and battery electric vehicle ownership is expanding, there is a growing need for widely distributed publicly accessible charging stations, some of which support faster charging at higher voltages and currents than are available from domestic supplies. Many charging stations are on-street facilities provided by electric utility companies, mobile charging stations have been recently introduced. Some of these special charging stations provide one or a range of heavy duty or special connectors and/or charging without a physical connection using parking places equipped with inductive charging mats.

As of December 2012, there were around 50,000 non-residential slow charging points and about 2,000 fast charges deployed in the U.S., Europe, Japan and China. As of March 2013, the United States had 5,678 public charging stations across the country with 16,256 public charging points, of which 3,990 were located in California, 1,417 in Texas and 1,141 in Washington. As of November 2012, about 15,000 charging stations had been installed in Europe. As of March 2013, Norway, the world's leader in electric car ownership per capita, had 4,029 charging points and 127 quick charging stations. As of December 2012, Japan had 1,381 public quick-charge stations, the largest deployment of fast chargers in the world, but only around 300 slow chargers. As of December 2012, China had around 800 public slow charging points, and no fast charging stations. As of December 2012, the country with the highest ratio of quick charges to electric vehicles (EVSE/EV) was Japan, with a ratio of 0.030, and the Netherlands had the largest ratio of slow EVSe/EV, with more than 0.50, while the U.S had a slow EVSe/EV ratio of 0.20.

Overview

Public-domain European charge station sign

U.S. traffic sign used for EV charging station

A charging station in Monza, Italy

Safety

Although most rechargeable electric vehicles and equipment can be recharged from a domestic wall socket, a charging station is usually accessible to multiple electric vehicle (EV) owners and has additional current or connection sensing mechanisms to disconnect the power when the EV is not actually charging. This is in case an EV should be carelessly driven away before being unplugged, and so violently rip away the charging cable insulation and expose the electric conductors, which (except for the sensor mechanism) could be dangerous.

There are two main types of safety sensor:

• additional physical 'sensor wires' which provide a feedback signal such as specified by the undermentioned SAE J1772 and IEC 62196 schemes that require special (multi-pin) power plug fittings,
• Current sensors which monitor the power consumed, and only maintain the connection if the demand is within a "window" (for example between 1 ampere and 15 amperes).

Sensor wires react more quickly, have less parts to fail and are possibly less expensive to design and implement. Current sensors however can use standard connectors and can readily provide an option for suppliers to monitor or charge for the electricity actually consumed.

Standards

In SAE terminology, 240 volt AC charging is known as level 2 charging, and 500 volt DC high-current charging is known as DC Fast Charge. Owners can install a level 2 charging station at home, while businesses and local government provide level 2 and DC Fast Charge public charging stations that supply electricity for a fee or free.

The International Electrotechnical Commission (IEC) modes are similar:

• Mode 1 - slow charging from a regular electrical socket (1- or 3-phase)
• Mode 2 - slow charging from a regular socket but which equipped with some EV specific protection arrangement (e.g., the Park & Charge or the PARVE systems)
• Mode 3 - slow or fast charging using a specific EV multi-pin socket with control and protection functions (e.g., SAE J1772 and IEC 62196)
• Mode 4 - fast charging using some special charger technology such as CHAdeMO.

There are also three connection cases with which mode is sometimes confused

• Case A is any charger connected to the mains (the mains supply cable is usually attached to the charger) usually associated with modes 1 or 2
• Case B is an on-board vehicle charger with a mains supply cable which can be detached from both the supply and the vehicle - usually mode 3
• Case C is a dedicated charging station with DC supply to the vehicle. The mains supply cable may be permanently attached to the charge-station such as in mode 4.

And finally there are four plug types

• Type 1 - single phase vehicle coupler - reflecting the SAE J1772/2009 automotive plug specifications
• Type 2 - single and three phase vehicle coupler - reflecting the VDE-AR-E 2623-2-2 plug specifications
• Type 3 - single and three phase vehicle coupler equipped with safety shutters - reflecting the EV Plug Alliance proposal
• Type 4 - fast charge coupler - for special systems such as CHAdeMO

Mode 1: Household socket and extension cord

Mode 1 : Fixed, non-dedicated socket.

The vehicle is connected to the power grid through standard socket-outlets present in residences, which depending on the country are usually rated at around 10 A. To use mode 1, the electrical installation must comply with the safety regulations and must have an earthing system, a circuit breaker to protect against overload and an earth leakage protection. The sockets have blanking devices to prevent accidental contacts. This solution is the simplest and the most direct to implement. It offers the driver the option of charging his /her vehicle almost everywhere, which guarantees the peace of mind for the first-time buyers of electric vehicles. However, this solution may pose risks if used incorrectly and has several serious limitations which has led to the definition of other more efficient charging modes.

The first limitation is the available power, to avoid risks of

• heating of the socket and cables following intensive use for several hours at or near the maximum power (which varies from 8 to 16 A depending on the country)
• fire or electric injury risks if the electrical installation is obsolete or if certain protective devices are absent.

The second limitation is related to the installation's power management

• as the charging socket shares a feeder from the switchboard with other sockets (no dedicated circuit) if the sum of consumptions exceeds the protection limit (in general 16 A), the circuit-breaker will trip, stopping the charging.

All these factors impose a limit on the power in mode 1, for safety and service quality reasons. This limit is currently being defined, and the value of 10 A appears to be the best compromise. At this power, it will take nearly 10 hours to fully charge a vehicle.

No dedicated circuit

For instance, in France, the local standard NF-C-15100 standard on installation allows the connection of several household socket-outlets into the same protective element of the dwelling's electrical switchboard:

• Up to 5 socket-outlets with a cable with a cross-section 1.5 mm².

Protection by a 16 A circuit breaker.

• Up to 8 socket-outlets with a cable with a cross-section 2.5 mm².

Protection by a 20 A circuit breaker.

It is therefore highly probable that the household socket used for charging an electric vehicle is on the same circuit as another electrical appliance, which may also be in operation during the charging.

In this case, the OCP, Overcurrent Protective Device, will open for safety reasons, as the cumulated currents of the electric vehicle and the household appliance will be higher than its setting threshold. Installation of a dedicated circuit for electric vehicle charging can prevent this type of unwanted tripping. Ensuring that any load or appliances on the shared EV charging circuit are turned off while charging, can prevent the OCP from tripping as well. This can be difficult to ensure, so a dedicated circuit is the most reliable solution.

Temperature derating and intensive use

Fully electric vehicles have charging powers varying from 3 to 24 kW. These powers correspond to charging currents from 16 A single-phase up to 32 A three-phase. Moreover, charging the vehicle may take up to 8 hours, and this has to be done regularly, even on a daily basis.

The NF-C-15100 standard imposes cable cross-sections of 1.5 mm² or 2.5 mm². Their maximum permissible power is 3.7 kW for a 1.5 mm² cable and up to 5.7 kW for a 2.5 mm² cable.

Household sockets are designed to be used at full load only for a limited period (typically 1 hour at maximum power, which is the case when we use household appliances). When charging an electric vehicle, the charging time exceeds this limit and can last up to 6 or 8 hours. Household sockets must therefore be classified as derating systems for this use case: Typically, for continuous use, ratings are reduced to 80% of specified amperage. Thus, a typical house with a 220v 20A circuit would be derated to 16A continuous duty. 40A would derate to 32A, etc. EVSE manufacturers, aware of these rules, typically will rate equipement to the breaker needed before derating. So an EVSE capable of delivering 48A to the EV, will be labeled and specified to require a 60A breaker, even though it will be drawing 48A.

Obsoleteness and non-compliance

In France, electrical installation professionals believe that there are about 7 million hazardous electrical installations (obsolete, non-compliant, etc.), accounting for a little less than half of the old residential building stock.

For instance in France, from 1972 onwards, new electrical installations are subject to an inspection and an attestation of compliance. This measure instituted by public authorities was extended in 2001 to the electrical installations of fully renovated dwellings.

However, the electrical installations of the 16 million dwellings built before 1972 are not covered by any regulatory control measure.

There are also misgivings about the condition of electrical installations in the dwellings built after 1972: according to electrical safety experts, an installation in which no change has been made for the last 30 years can be considered as obsolete. They further believe that, after thirty years, even in normal usage conditions, an electrical installation may most likely pose hazards due to wear and tear if no maintenance operation has been carried out since it was set up.

Connecting an electric vehicle without any precaution to this type of installation can therefore be dangerous for people and property when appropriate protective devices are absent.

Mode 2: Domestic socket and cable with a protection device

Mode 2 : Non-dedicated socket with cable-incorporated protection device.

The vehicle is connected to the main power grid via household socket-outlets. Charging is done via a single-phase or three-phase network and installation of an earthing cable. A protection device is built into the cable. This solution is particularly expensive due to the specificity of the cable.

Mode 3: Specific socket on a dedicated circuit

Mode 3 : Fixed, dedicated circuit-socket.

The vehicle is connected directly to the electrical network via specific socket and plug and a dedicated circuit. A control and protection function is also installed permanently in the installation. This is the only charging mode that meets the applicable standards regulating electrical installations. It also allows load-shedding so that electrical household appliances can be operated during vehicle charging or on the contrary optimise the electric vehicle charging time.

Mode 4: Direct current (DC) connection for fast recharging

Mode 4 : CC Connexion.

The electric vehicle is connected to the main power grid through an external charger. Control and protection functions and the vehicle charging cable are installed permanently in the installation.

Evolution

The coordinated development of charging stations in a region by a company or local government is more fully discussed in the electric vehicle network article. Currently charging stations are being installed by public authorities, commercial enterprises and some major employers in order to stimulate the market for vehicle that use alternative fuels to gasoline & diesel fuels. For this reason most charge stations are currently either provided gratis or accessible to members of certain groups without significant charge (e.g. activated by a free "membership card" or by a digital "day code").

Charging time

The battery capacity of a fully charged electric vehicle from electric vehicle automakers (such as Nissan) is about 20 kWh, providing it with an electrical autonomy of about 100 kilometres. Tesla Motors released their Model S with battery capacities of 40 kWh, 60 kWh and 85 kWh with the latter having an estimated range of approximately 480 km. Chargeable hybrid vehicles have capacity of roughly 3 to 5 kWh, for an electrical autonomy of 20 to 40 kilometres (the gasoline engine ensures the autonomy of a conventional vehicle).

As this autonomy is still limited, the vehicle has to be charged every 2 or 3 days on average. In practice, drivers plug in their vehicles each night, thus starting each day with a full charge.

For normal charging (3 kW), car manufacturers have built a battery charger into the car. A charging cable is used to connect it to the electrical network to supply 230 volt AC current. For quicker charging (22 kW, even 43 kW and more), manufacturers have chosen two solutions: - use the vehicle's built-in charger, designed to charge from 3 to 43 kW at 230 V single-phase or 400 V three-phase. - use an external charger, which converts AC current into DC current and charges the vehicle at 50 kW.

Charging time	Power supply	Voltage	Max current
6–8 hours	Single phase - 3,3 kW	230 VAC	16 A
2–3 hours	Three phase - 10 kW	400 VAC	16 A
3–4 hours	Single phase - 7 kW	230 VAC	32 A
1–2 hours	Three phase - 24 kW	400 VAC	32 A
20–30 minutes	Three phase - 43 kW	400 VAC	63 A
20–30 minutes	Direct current - 50 kW	400 - 500 VDC	100 - 125 A

The user finds charging an electric vehicle as simple as connecting a normal electrical appliance; however to ensure that this operation takes place in complete safety, the charging system must perform several safety functions and dialogue with the vehicle during connection and charging.

Infrastructure

Project Better Place charging stations in Ramat Hasharon, Israel, north of Tel Aviv.

Public charging station in a parking lot near Los Angeles International Airport. Shown are two old-style (6kW level2) EVSE units (left: inductive Magne-charge gen2 SPI, right: conductive EVII ICS-200 AVCON.

REVAi/G-Wiz i charging from an on-street station in London.

Charging stations for electric vehicles may not need much new infrastructure in developed countries, less than delivering a new alternative fuel over a new network. The stations can leverage the existing ubiquitous electrical grid and home recharging is an option. For example, polls have shown that more than half of homeowners in the USA have access to a plug to charge their cars.^{[citation needed]} Also most driving is local over short distances which reduces the need for charging mid-trip. In the USA, for example, 78% of commutes are less than 40 miles (64 km) round-trip. Nevertheless, longer drives between cities and towns require a network of public charging stations or another method to extend the range of electric vehicles beyond the normal daily commute. One challenge in such infrastructure is the level of demand: an isolated station along a busy highway may see hundreds of customers per hour if every passing electric vehicle has to stop there to complete the trip. In the first half of the 20th century, internal combustion vehicles faced a similar infrastructure problem.

Smart grid communication

Recharging a large battery pack presents a high load on the electrical grid, but this can be scheduled for periods of reduced load or reduced electricity costs. In order to schedule the recharging, either the charging station or the vehicle can communicate with the smart grid. Some plug-in vehicles allow the vehicle operator to control recharging through a web interface or smartphone app.^{[citation needed]} Furthermore, in a Vehicle-to-grid scenario the vehicle battery can supply energy to the grid at periods of peak demand. This requires additional communication between the grid, charging station, and vehicle electronics. SAE International is developing a range of standards for energy transfer to and from the grid including SAE J2847/1 "Communication between Plug-in Vehicles and the Utility Grid". ISO and IEC are also developing a similar series of standards known as ISO/IEC 15118: "Road vehicles -- Vehicle to grid communication interface".

Deployment of public charging stations

Locations

Charging stations can be found and will be needed where there is on-street parking, at taxi stands, in parking lots (at places of employment, hotels, airports, shopping centers, convenience shops, fast food restaurants, coffeehouses etc.), phone booths, as well as in driveways and garages at home. Existing filling stations may also become or may incorporate charging stations. Stations can be added onto other public infrastructure that have an electrical supply, such as phone booths and smart parking meters.

Anxiety regarding range and finding charging stations can be a major concern for EV drivers; this can be alleviated with online directories such as EV-Networks. Additionally, some charging station providers such as POD Point in the UK publish live availability of their charging locations for EV drivers.

In the UK most charging points have highly visible indicator lights to indicate whether it is available, charging or out of service.

Vehicle and charging station projects and joint ventures

Wireless charging station

Detail of the wireless inductive charging device

Main article: Electric vehicle network

Electric car manufacturers, charging infrastructure providers, and regional governments have entered into many agreements and ventures to promote and provide electric vehicle networks of public charging stations.

The EV Plug Alliance is an association of 21 European manufacturers which proposes an alternative connecting solution. The project is to impose an IEC norm and to adopt a European standard for the connection solution with sockets and plugs for electric vehicle charging infrastructure.

Members (Schneider Electric, Legrand, Scame, Nexans, etc.) argue that the system is safer because they use shutters. General consensus is that the IEC 62196 and IEC 61851-1 already have taken care of safety by making parts not touchable when live.

List of EV charging station companies

The principal suppliers and manufacturers of charging stations offer a range of options from simple charging posts for roadside use, charging cabinets for covered parking places to fully automated charging stations integrated with power distribution equipment

Charging station manufacturers

These companies design and manufacture charging stations.

DC charging stations (fast)

Tesla Model S charging at a Tesla Motors Supercharger network (rapid-charging) station in Gilroy, California.

Tesla Supercharger network rapid charging station in Tejon Ranch, California. The rooftop of the carport has a solar collector manufactured by Solar City feeding energy into the grid.

These companies (among AC slow-charging stations) design and manufacture DC Fast charging stations (less than 30 minutes). These systems may offer a restricted charge (stops at 80% SOC), or changes charging rate to a lower level after the 80% SOC is reached.

• Eaton (Stations with CHAdeMO and SAE Combined Charging System CCS) (US and Canada) up to 1MW.
• EFACEC (Stations with CHAdeMO and CCS (E.U. or U.S.) (CCS)
• ABB (Stations with CHAdeMO and CCS)
• AeroVironment
• Fuji Electric and
• Schneider Electric
• Signet Systems
• Delta Electronics and (Stations with CHAdeMO certified)

Other manufacturers

Companies that do not build and manufacture DC charging stations, but instead build slow-charging (AC) stations or re-brand fast charging stations produced by others.

• Etrel
• EvStations.net
• Coulomb Technologies
• PARVE Charging System A Spanish design
• SemaConnect A US maker of Charge Pro Level 1 outlets
• IAV A German design for an In-Road Electric Vehicle Charger
• OpConnect Electric Vehicle Charging System
• Clipper Creek

Charging network operators

An operator manages charging stations.

• ChargePoint
• ECOtality
  • Blink Network
• Better Place

EV charging station signs

In the United States, the standard charging station sign is defined in the Federal Highway Administration's Manual on Uniform Traffic Control Devices (MUTCD) 2009 edition.

See two examples of "D9-11b Electric Vehicle Charging" and "D9-11bP Electric Vehicle Charging" at "Figure 2I-1. General Service Signs and Plaques", page 301, Sect. 2I.02

There is an open source, public domain European charge station sign proposed.

Block heater power supplies

In colder areas such as Finland, some northern US states and Canada there already exists some infrastructure for public power outlets provided primarily for use by block heaters and set with circuit breakers that prevent large current draws for other uses. These can sometimes be used to recharge electric vehicles, albeit slowly. In public lots, some such outlets are only turned on when the temperature falls below -20°C, further limiting their use.

Battery swapping

A charging station is different from a battery switch station, which is a place to swap a discharged battery or battery pack for a fully charged one, saving the delay of waiting for the vehicle's battery to charge. Battery swapping is common in warehouses using electric forklift trucks. The concept of exchangeable battery service was first proposed as early as 1896 in order to overcome the limited operating range of electric cars and trucks. It was first put into practice by Hartford Electric Light Company through the GeVeCo battery service and was initially available for electric trucks. The vehicle owner purchased the vehicle from General Vehicle Company (GVC, a subsidiary of the General Electric Company) without a battery and the electricity was purchased from Hartford Electric through an exchangeable battery. The owner paid a variable per-mile charge and a monthly service fee to cover maintenance and storage of the truck. Both vehicles and batteries were modified to facilitate a fast battery exchange. The service was provided between 1910 to 1924 and during that period covered more than 6 million miles. Beginning in 1917 a similar successful service was operated in Chicago for owners of Milburn Light Electric cars who also could buy the vehicle without the batteries. A rapid battery replacement system was implemented to keep running 50 electric buses at the 2008 Summer Olympics.

The companies Better Place, Tesla Motors, Mitsubishi Heavy Industries and others considered working in integrating battery switch technology in their electric vehicles to extend their driving range. Better Place used the same technology to swap batteries that F-16 jet fighter aircraft use to load their bombs.

Better Place's battery switching station in Israel

In a battery switch station, the driver does not need to get out of the car while the battery is swapped. Battery swap depends on at least one electric car designed for "easy swap" of batteries. However, electric vehicle manufacturers that are working on battery switch technology have not standardized on battery access, attachment, dimension, location, or type.

The Better Place network was the first modern commercial deployment of the battery switching model. The Renault Fluence Z.E. was the first electric car enable with switchable battery technology available for the Better Place network in operation in Israel and Denmark. Better Place launched its first battery-swapping station in Israel, in Kiryat Ekron, near Rehovot in March 2011. The battery exchange process took five minutes. As of December 2012, about 600 Fluence Z.E.s were sold in the country. Sales during the first quarter of 2013 improved, with 297 cars sold, bringing the total fleet in Israel close to 900. As of December 2012, there were 17 battery switch stations fully operational in Denmark enabling customers to drive anywhere across the country in an electric car. Fluence Z.E. sales totaled 198 units through December 2012.

Better Place filed for bankruptcy in Israel in May 2013. The company's financial difficulties were caused by the high investment required to develop the charging and swapping infrastructure, about US$850 million in private capital, and a market penetration significantly lower than originally predicted by Shai Agassi. Less than 1,000 Fluence Z.E. cars were deployed in Israel and around 400 units in Denmark. Under Better Place's business model, the company owns the batteries, so the court liquidator will have to decide what to do with customers who do not have ownership of the battery and risk being left with a useless car.

Battery swapping has the following benefits:

• Fast battery swapping in as little as 59.1 seconds.
• Unlimited driving range where there are battery switch stations available.
• The driver does not have to get out of the car while the battery is swapped.
• The driver does not own the battery in the car, transferring costs over the battery, battery life, maintenance, capital cost, quality, technology, and warranty to the battery switch station company.
• Contract with battery switch company could subsidize the electric vehicle at a price lower than equivalent petrol cars.
• The spare batteries at swap stations could participate in vehicle to grid storage.^{[citation needed]}

Renewable electricity and RE charging stations

See also: Solar-charged vehicle

Charging stations are usually connected to the electrical grid, which often means that their electricity originates from fossil-fuel power stations or nuclear power plants. Solar power is also suitable for electric vehicles. SolarCity is marketing its solar energy systems along with electric car charging installations. The company has announced a partnership with Rabobank to make electric car charging available for free to owners of Tesla Motors' vehicles traveling on Highway 101 between San Francisco and Los Angeles. Other cars that can make use of same charging technology are welcome.

Several Chevrolet Volts at a charging station powered with solar panels in Frankfort, Illinois.

SPARC station

The SPARC (Solar Powered Automotive ReCharging Station uses a single custom fabricated monocrystalline solar panel capable of producing 2.7 kW of peak power to charge pure electric or plug-in hybrid to 80% capacity without drawing electricity from the local grid. Plans for the SPARC include a non-grid tied system as well as redundancy for tying to the grid through a renewable power plan. This supports their claim for net-zero driving of electric vehicles.

E-Move charging station

The E-Move Charging Station is equipped with eight monocrystalline solar panels, which can supply 1.76KWp of solar power. With further refinements, the designers are hoping to generate about 2000KWh of electricity from the panels over the year.

Wind-powered charging station

In 2012, Urban Green Energy introduced the world's first wind-powered electric vehicle charging station, the Sanya SkyPump. The design features a 4 kW vertical-axis wind turbine paired with a GE WattStation.

See also

• Automated charging machine
• Battery charger
• Battery leasing
• Direct coupling
• Dump charging
• Electric vehicle battery
• Electric vehicle network
• EV Project
• Filling station
• IAV
• In-road electric vehicle charger
• Lamppost
• List of energy storage projects
• Magne Charge
• Park & Charge
• Plug-in vehicle
• Plug-in hybrid vehicle
• Plugless Power
• RFID
• SAE J1772 and CHAdeMO charging standards
• Solar-charged vehicle
• Transport electrification
• V2G, V2Green and V2H

External links

• chargelocator.com - Find world wide charging stations for free (Web/iPhone/iPad/Android/Windows8)
• Alternative Fueling Station Locator (EERE): US charging stations.
• Electromaps - Recharge points for electric vehicles Find where recharge your electric vehicle
• EV Charger News - website/mailing list
• UK directory of charge points / charging stations.
• PlugShare - community-driven site of charging stations
• Plug-In Charging Stations List of US Charging station networks and phone numbers
• Description of the EVITP or Electric Vehicle Infrastructure Training Program, via a PDF file from the DOE's web site.
• openchargemap - Charging stations around the world.
• chargestations.info - Search for Public Charging Stations around the US.