I am producing way too much power from my solar panels. A 15 kWh battery is an $18,000 investment. I worked out that at the 12 cents differential between what I get paid for export and what I pay for import it would take 41 years to pay off the battery if I used all of its capacity every day. No payback and the battery won’t last that long.
Then looked at used Leaf batteries and some of the BSMs created to manage them as a poor man’s Tesla Powerwall 2. Too risky. But then I thought, my EV has 54 kWh. Why can’t I just use its battery?
Thanks for getting in touch. While we haven’t ruled out the development of a bi-directional charger, we do not have any current plans to release one.
Almost all bi-directional chargers are DC, with the exception of some bi-directional AC charging trials being done by Renault. One of the issues with DC is that it is typically much more expensive, which is a key consideration especially in your case when you are considering payback time. My understanding is that the Wallbox Quasar will be retailing for somewhere in the range of $7,000 - $10,000 NZD, once it is availalble here, though you would have to check with the local distributor.
To optimise self-consumption, the low hanging fruit is to ensure that you’re charging your car when your solar is generating, instead of the evening. In early September we will have our Gecko Power Sensor available (compatible with Evnex E&X Series) which can automatically divert excess solar into your car. If you’d like to know more about it, please get in touch at sales@evnex.com.
I also am hoping for bi-directional charging.
In the next couple of years I am planning to upgrade my Leaf and hoped then to be able to charge it from our solar panels or at least at night when power is cheaper and use the car’s battery when power is charged at peak rate. At present when the car battery is full and there is no need in the house all I can do is sell it to the grid at 14c per unit
Apparently this will all take quite a bit of time. There are trials in Oz and some here in NZ with Leaf cars in V2H and V2G modes but regulations currently do not permit this. In fact you could be classed as a generator in the NZ market and have the hundreds of thousands of dollars of reporting costs to manage. he law of course will change, but slowly as the power companies are of course not going to support this form of energy generation and supply. Then you need all the fast acting switchgear to disconnect your house from the grid so that your car does not drain down supplying your local area in the case of a power cut… Lots of water under bridges before I see V2H solutions really taking off, which is a shame as my current EV has 76 kWh of storage.
We are about to upgrade our PV from 5kW to 8.5kW to better supply our 7kW JuicePoint EV charger. Our likely installer has recommended an Evnex EVSE to enable sole use of PV generation for EV charging but we also considered adding battery storage to our system. It seems to us that spending ~$20K on static batteries is shortsighted when we have the battery capacity of 2 EVs available that could potentially fulfill the same purpose if used in a V2G capacity. This would of course make an Evnex E2 EVSE redundant and possibly the better approach would be to persist with the JuicePoint charger in the interim.
Is there any further news on Evnex adding a bidirectional EVSE to their range?
There has been progress on the standardisation front, but still not enough for us to be confident to launch a product. It’s not yet clear exactly how the cars will support this, and whether the connection to the vehicle will be DC (with the inverter on the wall) or AC (with the inverter in the car). My suspicion is that existing cars are unlikely to have the relevant hardware to comply with the eventual standard.
The requirements of the charger would be wildly different under those two scenarios, which is why most of the examples that you see in trials today are set up for use with a specific model of car in a specific setting - not something that lends itself well to a consumer product with wide application and a price point that we would be comfortable with.
If you were to ask me to gaze into my crystal ball I would say that V2G isn’t going to be in use at scale for at least 3-5 years (that’s a personal view and may not be shared by everyone at Evnex!)
Obviously I’m biased, but I think the E2 is great and you won’t be disappointed should you choose that route! It will also play nicely with your JuicePoint and slow itself down to prevent home overload if both EVs are charging at the same time.
Hi Tom, reading through this string of posts and being 7months+ since your reply to Organix - can you advise if there has been any updates from your end on Bidirectional charging and whether Evnex can/will develop this? As you know we have 2 x22 units installed (work & home) and the BYD Seal which has V2L capability is sitting in my garage of a night with over 70kWh of battery most nights, just sitting idle… I agree with the other posters - there’s not much sense buying a Tesla Powerwall or equivalent when in reality we already have 5+ Poweralls already in place?? My other question (ignorant perhaps) - can your current x22 chargers be retrofitted do you think to be BiDirectional or would it mean a whole new charging unit? Interesting too that since the 1st post in this stream - FIT’s have dropped even further and we’re currently getting $0.08 per kWh which is now one of the better rates! Really hope you guys have some options soon. Cheers Ben
The standards are now sufficiently advanced that we have begun some technical work that will underpin an eventual bidirectional charger. It definitely won’t be something that would fit into our existing units so it would mean a whole new charger.
V2L is an interesting technology that is great for backup of a few appliances in the event of a power cut, but my understanding is it’s not likely that it will lead to a vehicle being ready for V2G. In a V2L scenario the car itself is producing the AC waveform in complete isolation so it doesn’t have to match the grid, but to do V2G you need to be able to synchronise perfectly with what’s already there so it’s a significantly harder problem. In addition there are numerous regulations around connecting “generation” to the grid, none of which need to be met for V2L. I could be completely wrong about that though (unlike the hardware team at Evnex I’m not familiar with all the relevant standards) so definitely take it with a pinch of salt!