Electric vehicles are gaining momentum on a worldwide basis. A compatible charging infrastructure and communication between the vehicle and the "charging spots" is required for ease of use on the end user side. The already established Power Line Communication (PLC) standard in the Smart Power Grid area offers a robust and long term available setup.
Electric cars, with a history ranging back more than hundred years, are experiencing a renaissance. The rise in fuel costs, improved battery technologies and government incentives are just some of the factors that make electric vehicles (EVs) a great choice especially for individual mobility in the growing megacities.
China shows an impressive rollout plan, but also European countries are driving this trend. Germany has a plan for 1 million EVs by 2020; France is moving ahead even faster with massive government funding for a plan to install 1 million EV charging spots by 2015 and 2 million EVs by 2020. The increased distribution of EVs also offers new business opportunities for utility providers creating new income sources and also allows grid stabilization (cut of peak loads) via the EV's battery as buffer feeding energy back into the power grid.
The charging of these EV batteries can be done in different ways. The majority of the charging cycles will certainly happen at home or at work (estimated at 80%), but public charging spots are required as well to ensure an adequate supply grid.
There are different possibilities for charging. The most basic one is to use a single phase power supply of 230V and up to 32A AC via a typical 3 kW on-board-charger, but also via a 3 phase 400V with up to 63A AC (typical 20 kW charger). Charging with these currents is typically taking hours and is combined with parking times of the car (home, work, shopping). A closer equivalent of a gas station for conventional combustion engine cars is the DC charging (or also called fast charging) ranging up to 100 kW power, but this has to be possible without damaging the battery pack.
Ease of use
All of these charging situations in public drive the need for user interaction at the charging spot. For advanced features, the identification of the vehicle itself at the charging spot is required, which is typically realized via Power Line Communication (PLC). In these cases, a variety of data, including vehicle identification, current battery status, maximum allowed charge current and number of phases, charging times (e.g. delayed charging start), and overall 'charged' electricity amount with associated costs are exchanged. The identification of the car in the network opens up a cross utility provider usage of the electricity, similar like roaming in a mobile phone network.
However, this brings up one of the most important requirements: every car has to work with every charging spot. So the standardization does not only apply to the used plug standard, but also to the method of communication of the car with the charging infrastructure.
The PLC is a well suited choice as the connection cable is needed anyway for charging (excluding the possibility for inductive charging, which is lower power but under consideration). PLC is robust and does not normally require any additional user interaction.
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The logistics of the electric vehicle are the obstacle that stands in the way. The problem is fundamental physics: it takes quite a lot of energy to drive a car, and you must put that energy back into the battery sometime, or you stop. EVs are fine if only a few people on the block have them, but if there are a lot of them and they all defer their charging until the rates drop, then there will probably be an overload at the local step-down transformer. In order to handle everybody's electric car we would need a lot more distribution capacity, which is not cheap. The alternative is some invention that uses magic to cause the battery to "somehow become fully charged". Making the cars more efficient is going in the right direction, but the laws of physics still hold. So perhaps some kind of fuel cell, especially a fuel cell that could use hydrocarbon fuels directly, would be a better solution. A fuel cell that ran on diesel fuel would be the ultimate solution. So why not push research in that direction?
To contain pollution and to improve the efficiency of energy use, EV seems to be the best solution. I agree with Bert that having no garage and no electrical outlet at work would be the major stumbling block for NA to move forward. Parking lot charge station would be ideal. The extra revenue bring to the property owner would be a great incentive. Yet, the ultimate problems are how to charge and at the same time how to charging being stolen. Before finding a solution to the problems, regulation of deploying charge meter to parking lot shall be developed by government.
Leaf as well reveals another issue which is lack of mileage. Driving 200 miles is just not enough for NA.
At this point, hybrid car seems to be better solution until the advancement of battery technology and the readiness of infrastructure.
In England we used to have electric buses (Trolleybuses) that ran off 2 wires above the road with poles to collect the current. This could charge-as-you drive on the freeway but the possibilites for chaos are of course endless with the average public.
The recent article on the Nissan leaf brought up this charging problem. Especially acute if you don't have a garage or at least a home with off-street parking.
When away from home, e.g. parked in the garage at work, I think the benefit of a smartgrid would be primarily for identifying the car and charging (pun intended) the driver for the juice. However, drawing lots of power from the grid during the work day is certainly not ideal, from the standpoint of power generation and distribution. That's when electricity demand is at its peak already. And communities are already up in arms about allowing the electric utilities to erect more high tension lines in their neighborhoods.
So I think people need to do some more analysis, before jumping on this battery-powered electric car bandwagon. These plans for 230 VAC outlets at shopping malls and everywhere else just seem unlikely to me.
I'd be looking more seriously at storing the energy as a liquid hydrocarbon fuel, just like any car, and then separating the H2 on-board, for use in fuel cells and all-electric drives. That would bring electric cars to the realm of the probable.