Volkswagen has released a small-sized 22kW DC charging dock that can be installed at home or offices, and requires only half of the charging time of the existing general AC charging stations, though will this charging method with moderate speed actually be useful?
Volkswagen will commence a testing program in 5 cities in Germany, which comprises of installing a small-sized DC wall-mounted charging dock for users and companies that has a power of 22kW, which is almost two times faster than the general AC charging stations at 7-11kW.
▲The water heater-like object on the right is the tested DC charger.
There are currently three main charging methods for electric vehicles, each with different usage scenario and restrictions.
The slowest and simplest method is using a portable charging cable that charges the vehicle when plugged into the socket at home. The power is at 1.5kW if calculated according to the 110V voltage in Taiwan, which is suitable for temporary power replenishment, and will not be optimal as the primary charging method.
The second method is the commonly seen public charging stations that adopt the AC approach, and is able to achieve a maximum power of 11kW, with a more common power level at 7kW in Taiwan. The household charging station provided by electric vehicle manufacturers usually come in this form, and 6-8 hours are generally required for a full charge to 100%.
The third method is the fastest yet most troublesome DC fast charge station (referred to as the Supercharger by Tesla), which has a minimum of 50kW of power, and the third generation of Tesla’s Supercharger can achieve a maximum power of 250kW, whereas Porsche has the highest 800kW fast charge technology in the current market. Generally speaking, a fast charge station can charge up to 80% of battery within 30 minutes, which is suitable for replenishing on battery for long distance travels.
The small-sized DC charger of Volkswagen is categorized between the second and third method, with a moderate charging speed, and is neither cheap nor expensive. The good thing about adopting DC is that it facilitates bilateral charging, which resembles of putting an additional large battery at home for households that occupy a large ratio of renewable energy, and is able to regulate power.
There is always a fine line between moderation and uselessness. If you have an AC charging station at home that charges to full battery every night, then the time preserved doesn’t actually mean much, though if you are a regular vehicle user, then this equipment will be of much use. Another possible usage scenario would be the car park of shopping malls, where users usually linger for no more than 2 hours, so the degree of power replenishment is restricted even if a charging spot is obtained. Don’t be too happy if there is a large-sized fast charge station in the shopping mall, since you will be asked to drive away your vehicle once it is fully charged after 20 minutes.
Perhaps the “neutral charging” method can find purposes in certain scenarios, and even resolve numerous issues, though it will eventually have to depend on the cost of installation and the degree of support from the power grid. Volkswagen will obtain data from the 20 testing units within the next 6 months that will be used for the evaluation in the potential commercial operation. Volkswagen ID. 4 and Audi e-tron are very likely to be the electric vehicle models to first support this particular function, should it become available in the future.
(Cover photo source: Volkswagen)