The idea is indeed awesome. The following is in relation to current state.
Current technology implementation is not yet suitable for the home application, though. This is primarily due to inefficiency. Most systems run 70-80% efficiency, with the best only achieving about 85%, and those are expensive due to the precision engineering required (small coil sizes running high frequency). From a cost-perspective, paying for 25% (75% efficiency) lost energy isn't appealing. For cost, in real terms against the BMW i3 battery:
80% efficiency:
- 22kWh total; 18.8kWh usable
- 80% efficiency to charge 18.8kWh = 3.76kWh loss (22.56kWh total electricity draw)
- At .14 cents/pence per kWh, that's .53 cents/pence extra cost to charge. Multiplied by charging 5 days a week for a year and it is 136.86.
70% efficiency:
- 22kWh total; 18.8kWh usable
- 70% efficiency to charge 18.8kWh = 5.64kWh loss (24.44kWh total electricity draw)
- At .14 cents/pence per kWh, that's .79 cents/pence extra cost to charge. Multiplied by charging 5 days a week for a year and it is 205.30.
Those numbers just aren't nice for additional cost to charge, nevermind that doesn't consider initial cost for the tech. As reference, most people report about 10% loss for plug-in charging at level 2 and about 5% for level 3.
As with anything, as technology improves to bring initial cost down and improve efficiency, wireless is definitely appealing. We park in our garage every night, in virtually the exact positioning (wood blocks on the floor to come up to after having to come in at a very specific, precise angle to fit into the garage door), so being able to just pull in and walk away would be brilliant.
