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Charge metering for outlets and wall connectors

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user212_nr

Active Member
Aug 26, 2019
1,407
887
US
I was thinking that someone needs to invent a cheap way to bill users for electricity. Right now, people are just giving away electricity to EV owners; instead of paying to install an expensive ChargePoint type system, they say "here's an outlet". Its not really an incentive to EV owners because they already bought the EV, and this puts limits on how many EVs they can support.

At the very minimum, a device is needed < $100 that can
a) connect to the internet (WiFi, LTE, or ethernet)
b) turn on/off power to an outlet
c) identify a user and bill them (bluetooth/app?)
d) take a fee to support the server infrastructure
e) pay the owner of the station

I don't know how metering works, but the simplest way is to take the expected load on the circuit and bill them the number of minutes that it is "ON" and then disconnect the power when the minutes are up. A meter would better, but not if it costs $1,000 - maybe those current claps could be installed internally and counted electronically.

Then, instead of having "doing EV owners a favor", apartment owners can recoup their costs and make a small profit. So at its most basic level it will cost $100 plus the cost of installation of the outlet ($700?) and they can make back their cost in a year.

This is what chargepoint does, but it costs about $7,000 and they'd have to charge a lot to recoup those costs.

Someone with electronics experience should make this.
 
Turns out can be done with modular Arduino components.

Arduino w/ Ethernet ($40)
Electormagnetic relay 30A (MGN2C-AC240) $50
HiLetgo 2pcs ACS712 30A ($7.19)
Bluetooth (DSD TECH HC-05) $8.49

That makes $105.68 for the main parts of one unit. Plus maybe $5-$10 wires. Needs a plastic mounting case and electrician can install it in some waterproof location.

Sell it for $200 and take a 5-10% cut on all sales.
 
  • Informative
Reactions: APotatoGod
Be aware that many states have laws regulating who can charge for electricity; basically, you need to be a utility to do so. Charge station owners (including Tesla, for its Superchargers) get around this by charging by time rather than by kWh. Thus, if you were to try to implement something like this, either on a do-it-yourself basis or to create a product you could sell, you'd want to research the legal issues so as to avoid being sued or having your charging stations shut down by regulators.
 
  • Helpful
Reactions: MightyHawk
Be aware that many states have laws regulating who can charge for electricity; basically, you need to be a utility to do so. Charge station owners (including Tesla, for its Superchargers) get around this by charging by time rather than by kWh. Thus, if you were to try to implement something like this, either on a do-it-yourself basis or to create a product you could sell, you'd want to research the legal issues so as to avoid being sued or having your charging stations shut down by regulators.

I've heard of that. Time-metering has some advantages from a technical POV. You don't need to measure current, and can even run the machines without internet (pre-authorize through the smartphone). Disadvantage is that the user can get billed for more than asked for, has to estimate how long they will be, etc.

Legal issues are many with electronic - I suspect there are much more.