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Charge your EV (electric vehicle )at home?

2021-03-30

Charge your EV electric vehicle at home?

 

Are you planning to buy an electric vehicle or a plug-in hybrid, or are you at least thinking about it? But you don't yet know exactly how to charge the electric car at home?

We bring light into the darkness of the technical abbreviations and terms, the various plugs and cables as well as all additional costs arising in this topic.

We also dispel myths so that charging an electric car at homeworks as easily as brushing your teeth.

 

Charging an electric car at home - what do you need?

To recharge an electric car or a plug-in hybrid, you need a parking space with a  power connection & an EV Charger

 Ideally in the immediate vicinity, ideally right at home on your own property.

 

 

If long charging times of several hours are not an issue, the vehicle can be charged using a charging cable with an integrated control unit at a conventional 230 volt household socket . Said control device is known as an  in-cable control box, which comes from the term in-cable control box, or  ICCB for short .

This method is certainly the most convenient variant, but besides the long charging times it also has another disadvantage: The increased risk of a cable fire , as the in-house power supply is heavily used by this long-term load . Due to its low efficiency, this type of charging process is often referred to as "emergency charging".

A faster method is to connect to a power connection that is often already available in many households ( three-phase alternating current , also known as heavy current). With a charging voltage of 400 volts, the charging time is significantly reduced. A charging cable with ICCB is also required for this.

 

Alternative wall box

A much more convenient alternative to charging the vehicle is a wall box , which is also operated with 400 volts three-phase alternating current, but as an advantage the charging control has already been integrated into the wall box. Therefore an electric car specific charging cable without ICCB can be used.

The wall box is a name for a charging station according to IEC 62196 (international standard for connector types) which was specially developed for electric vehicles. A wall box is connected to the 400-volt power network as described. Depending on what the cables allow with 16 or 32 amps.

Since this power connection is already available in most households, as it is also used for kitchen stoves, among other things, this is the basic requirement for installing a wall box. The higher currents enable higher charging capacities of 11 to 22 kilowatts to be achieved, which significantly shortens the charging time.

However, the charging time also depends on the battery capacity of the corresponding battery itself. The greater the capacity of the battery, the longer the charging time for a full charge.

The installation should always be carried out by a specialist who at the same time clarifies whether all connections and cables can withstand this  constant load , as it can be charged with a current of up to 32 amps. Otherwise there is a risk of cable fire in the worst case .

The car is connected to the wall box via a charging cable with the type 2 plug, which is also called the Mennekes plug. The type 1 connector is also common among Asian car manufacturers such as KIA or Nissan .

 

Overview of different connector types

Below we want to give a brief overview of the different connector types. The electric car-specific connection according to the IEC 62196 type 1 or type 2 standard is always located on the vehicle itself  . There are then various options at the house connection that require the corresponding cable type.

· The standard plug (according to CEE 7/4) is also known as a household plug because it is the standard in German households. The charging power is around 2.3 kW at 230 volts and 10 amps. A connection cable with ICCB is required.

· The CEE blue plug (IEC 60309 standard) is also referred to as a "camping plug" because its robust nature means that it is often used in camping. The maximum charging power is 3.7 kW at 230 volts and 16 amps. A cable with ICCB is also required for this.

· Similar to the CEE blue plug, the CEE red plug (according to the IEC 60309 standard) is also used for continuous load. This connection is often referred to as a three-phase plugor three-phase plug. It is designed for 400 volts and 16 or 32 amps, so a charging power of up to 22 kilowatts is possible. Again, it only works with ICCB.

· The type 2 charging plug (standard IEC 62196) is also known as the Mennekes plug. Most wall boxes and public charging stations are equipped with this connection. The type 2 plug was specially developed for charging electric cars, as they exchange information between the car and the charging station in addition to electricity . In the 400 volt and 32 amp version, they have a charging capacity of 22 kilowatts. An ICCB is not necessary as the charging control is integrated in the wall box.

· Asian electric vehicles prefer to use the type 1 charging plug , which is designed for a single-phase three-wire network. This means that it can guarantee a maximum charging power of 7.4 kW with a single-phase charger. For the European market, this cable has a type 2 plug on one side and a type 1 plug on the other. The same applies here with regard to the charge control. 

 

 

Duration of a charging process

The duration of a charging process is influenced by two factors: the battery capacity and the charging technology . In addition, the condition of the battery does not play a minor role. This in turn is also dependent on external influences such as temperature.

The charging power depends on the voltage and current used. At the household connection (230 V) with 10 amps, the charging power is 2.3 kW. The charging process takes a correspondingly long time. A power of 22 kW can be used on a wall box (400 V) with 32 amps, which reduces the charging time accordingly.

Assuming a battery capacity of 20 kilowatt hours, the charging time is between six and eight hours at a normal household socket (230 volts and 10 amperes). With a wall box, the charging time is reduced to a total of around one hour. 

 

 

Charging: The "big" Nissan Leaf needs 13 hours on the 220 volt socket. At the wall box a good 5. 

This requires a three-phase charger in the car. If a vehicle only has a single-phase charger,  the charging process is limited to 7.4 kilowatts even on a 22 kilowatt wall box. In Germany, the output is even limited to just 4.6 kilowatts per phase in order  to prevent unbalanced loads in the power grid. If the 4.6 kilowatts are used, the battery would need around four to five hours to charge.

 

Costs per charging of the Electric car at home

Since some  electricity providers offer  cheaper night-time electricity , one should not shy away from a comparison and, if necessary, charge the electric vehicle preferably overnight. In such a case, it is necessary to install a separate  electricity meter at the charging point of the  electric car . With some wall boxes, this is already acquired with the purchase price.

 

A separate electricity meter would be necessary when using night-time electricity.

 

The costs for a wall box are between 500 and 1,900 USD , depending on the manufacturer and equipment . Attention : Some manufacturers of electric vehicles subsidize the purchase of a corresponding wall box when buying an electric car or even trade it as a free on-top . You should inquire about this at the respective manufacturer or dealer if you are interested in a specific model.

 

 

The topic of electric vehicle will be with us in the future. In addition to the wall box, other alternatives such as an inductive charging loop in the floor under the parking space should soon be added. We can be curious to see how the technology will develop further with regard to the topic of "charging electric cars at home".