EV charging from domestic renewable energy sources

quietsailor

Morning all,

I haven't bought an EV myself but have been following this forum with great interest as we're thinking of buying. Google or FB must have twigged that I'm interested in EVs because ads for EV related items are popping up in my feeds.

Among them is an indiegogo campaign (similar to kickstarter) for an EV charging point that can be connected into a house that has photovoltaic or wind turbine energy production and you can set the charger to only take the renewable energy or some combination of mains & renewables.

The company is called Zappi and here is the link to the indiegogo page Zappi Link

This image shows the 3 charging modes


EDIT: THis can be supplied by photo voltaic AND wind turbine renewable power sources according to the manafacturers. I'd imagine micro-hydro could be another power source.

2nd Edit - added the photo to make the different charging modes clearer

KCross

I dont see the benefit of it.
On the surface it seems like a great idea but its not actually that useful.

Most charging will be done at night when Solar PV will be producing nothing so it will just behave the same as a normal EVSE in the majority of cases.

If you are charging by day a Solar PV system would already have an in-built ability to give priority to the house demand (i.e. your car) first before it exported anything to the grid. So, what does this new EVSE do thats any better? I just dont see the benefit or novel element they claim they have.

They mention pausing charge if the PV power drops but thats not necessarily a good thing either. The EV is likely to not start its charge again when there is a break in the power input and I dont want to go out to find the car not ready because it was trying to be ECO. Again, I dont get the selling point.

quietsailor

KCross wrote: »

I dont see the benefit of it.
Most charging will be done at night when Solar PV will be producing nothing so it will just behave the same as a normal EVSE in the majority of cases

In case my first post wasn't clear I'll gone back and edit it -- it's not just solar PV that can be used as a power source, wind tubines can also be used so the car will become a storage device.
That seems to be the holy grail among renewable energy proponents at the moment as renewables can't increase/decrease power on demand as a engine powered generator can, instead they use times of low demand to charge up a storage and then in peak demand use the storage to increase supply

I'd imagine micro hydro can be used as well

KCross

quietsailor wrote: »

In case my first post wasn't clear I'll gone back and edit it -- it's not just solar PV that can be used as a power source, wind tubines can also be used so the car will become a storage device.
That seems to be the holy grail among renewable energy proponents at the moment as renewables can't increase/decrease power on demand as a engine powered generator can, instead they use times of low demand to charge up a storage and then in peak demand use the storage to increase supply

I'd imagine micro hydro can be used as well

I still dont get the point of it. Wind and/or Solar PV would still have the same characteristics in that the house gets priority first and the excess goes to the grid.

If you want to store the energy you would use something like a Tesla Powerwall, not the car.

I really wouldnt want the EVSE turning on and off its power to the car. Every morning I'd have range anxiety before I even get out of bed as I dont know if the wind was blowing or not.

I think a Feed In Tariff would make this product redundant.

zilog_jones

Yeah I'm not getting it either. If you want use the energy that you're generating to charge your car, you'd need some other intermediate storage as your car's not going to be plugged in all the time.

Dardania

I think I understand the point of it. It appears to be using a part of the type 3 charging spec, whereby the demand by the car for charging can be adjusted according to what power is available in the house spare. (be that a fed in renewable, or up to your MIC).

see load shedding portion here: https://en.wikipedia.org/wiki/Charging_station#Mode_3:_Specific_socket_on_a_dedicated_circuit
cros13 was talking about something related to this last year.

I think this is a cool idea. For those people with electric showers it could mitigate the need for priority switches...

KCross

Dardania wrote: »

I think I understand the point of it. It appears to be using a part of the type 3 charging spec, whereby the demand by the car for charging can be adjusted according to what power is available in the house spare. (be that a fed in renewable, or up to your MIC).

see load shedding portion here: https://en.wikipedia.org/wiki/Charging_station#Mode_3:_Specific_socket_on_a_dedicated_circuit
cros13 was talking about something related to this last year.

I think this is a cool idea. For those people with electric showers it could mitigate the need for priority switches...

It was @BoatMad that was working on a load shedding EVSE, which is a really good idea.
http://www.boards.ie/vbulletin/showpost.php?p=101564723&postcount=15

His idea was to monitor the total house load and shed the EVSE load to ensure you dont blow the main fuse.

Not sure this system is the same as it seems to be more about maximising Solar PV and Wind usage rather than load shedding to save fuses.

Maybe this is a mixture of those ideas.

Dardania

KCross wrote: »

Dardania wrote: »

I think I understand the point of it. It appears to be using a part of the type 3 charging spec, whereby the demand by the car for charging can be adjusted according to what power is available in the house spare. (be that a fed in renewable, or up to your MIC).

see load shedding portion here: https://en.wikipedia.org/wiki/Charging_station#Mode_3:_Specific_socket_on_a_dedicated_circuit
cros13 was talking about something related to this last year.

I think this is a cool idea. For those people with electric showers it could mitigate the need for priority switches...

It was @BoatMad that was working on a load shedding EVSE, which is a really good idea.
http://www.boards.ie/vbulletin/showpost.php?p=101564723&postcount=15

His idea was to monitor the total house load and shed the EVSE load to ensure you dont blow the main fuse.

Not sure this system is the same as it seems to be more about maximising Solar PV and Wind usage rather than load shedding to save fuses.

Maybe this is a mixture of those ideas.

sorry - you're right. and I must have wrongly addressed it to cros13 (which explains why I didn't receive 
any response on the thread!)

it sounds like they're overcomplicating their advertising, such that people might make the association that thier chargepoint is only valid if you have a renewable source. when in fact, there are other use cases. they should really include a simple diagram showing CTs & sources...

I'm going by this text from their spec sheet:
Here are the main features and benefits of zappi...

• 3 charging modes (Fast, Eco and Eco+)
• Boost function - keeps the battery at a minimum charge level
• Economy Tariff sensing to maximise savings
• 6A to 32A variable charging 
• Integral RCD for earth leakage protection
• IP65 rated enclosure suitable for outdoors
• Energy and savings data logging
• Graphical LCD screen for ease of use
• 5 metre, 32A rated cable with Type 1 or Type 2 charge plug
• Adjustable charge current limit - allows installation with smaller circuit breakers (e.g. 16A)
• Adjustable import power limit  - The maximum import limit can be set to limit power drawn by the house when charging
• In-line mounting holes for easy fixing to brick or timber stud walls
• Through-wall or surface mount cable entry options for easy wiring 

 
Zappi specifications
Dimensions: 362 x 220 x 78mm
Charging mode: Mode 3 (AC)
Maximum Charge Current: 32A (7kW)
Supply: 90-256V 16A or 32A 50/60Hz
Compliance: BS 8300:2009+A1:2010, BS EN 61851, BS EN 62196

quietsailor

Dardania wrote: »

it sounds like they're overcomplicating their advertising, such that people might make the association that thier chargepoint is only valid if you have a renewable source. when in fact, there are other use cases. they should really include a simple diagram showing CTs & sources...

I'm going by this text from their spec sheet:
Here are the main features and benefits of zappi...

• 3 charging modes (Fast, Eco and Eco+)
• Boost function - keeps the battery at a minimum charge level
• Economy Tariff sensing to maximise savings
• 6A to 32A variable charging 
• Integral RCD for earth leakage protection
• IP65 rated enclosure suitable for outdoors
• Energy and savings data logging
• Graphical LCD screen for ease of use
• 5 metre, 32A rated cable with Type 1 or Type 2 charge plug
• Adjustable charge current limit - allows installation with smaller circuit breakers (e.g. 16A)
• Adjustable import power limit  - The maximum import limit can be set to limit power drawn by the house when charging
• In-line mounting holes for easy fixing to brick or timber stud walls
• Through-wall or surface mount cable entry options for easy wiring 

 
Zappi specifications
Dimensions: 362 x 220 x 78mm
Charging mode: Mode 3 (AC)
Maximum Charge Current: 32A (7kW)
Supply: 90-256V 16A or 32A 50/60Hz
Compliance: BS 8300:2009+A1:2010, BS EN 61851, BS EN 62196

Thank you for quoting that from the webpage, I should have copied that in from Post1 to make things clearer.

The photo here shows the 3 types of charging Zappi are talking about;
[IMG][/img]
you can set the charger to use mains only if you have a worry that you need afull EV battery in the morning. This would be useful if it is a calm night and your renewable source is a wind turbine.
THe other 2 settings allow you to mix renewables and main power inputs which is useful if you've already installed renewables but aren't getting the best use out of them. This, I think is the whole idea of this charge point. It helps you maximise your efficency if you already have a renewables source and also have/are buying an EV

KCross

Real user!

KCross

I still don’t see much benefit in this product unless you have an unusual profile where your EV charging is regularly done during the day, which must be a small minority?


Another issue…
@BoatMad, you’ve done some work on a load shedding EVSE.

Have you confirmed with the current Leaf that it can dynamically increase the Amps it pulls based on what the EVSE makes available?

e.g.
- Charge starts at 6A and everything running fine
- Sun comes out from behind the clouds and now Solar PV has 12A available and the EVSE makes that available
- Will the Leaf utilise the increased power or will it stay at 6A?

I vaguely remember you saying that the EVSE charge protocol doesnt allow for the EVSE to “tell” the car to increase. All it does is negotiate a starting current and then the car decides itself after that.

So, does (as opposed to can) the Leaf increase power drawn during a charge cycle if it becomes available?

ted1

It or a variant of it could be handy if you are in a block chain.

unkel

KCross wrote: »

I still don’t see much benefit in this product unless you have an unusual profile where your EV charging is regularly done during the day

And even then, only if the home owner installed a massively oversized PV array. You would wonder why anyone would do that. Maybe hoping for a FIT, maybe hoping to install a battery once they get cheaper in a few years time?

And has no feed in tariff. Or more precise: has no FIT or a FIT that is lower than night rate. Otherwise why not charge the car at night and feed the excess solar to the grid?

Now obviously if this charger is only marginally more expensive than a normal 32A charger and you get 75% of the purchase and install price back in subsidies (UK), making if actually cheaper than a standard EVSE then why not?

Casati

unkel wrote: »

And even then, only if the home owner installed a massively oversized PV array. You would wonder why anyone would do that. Maybe hoping for a FIT, maybe hoping to install a battery once they get cheaper in a few years time?

And has no feed in tariff. Or more precise: has no FIT or a FIT that is lower than night rate. Otherwise why not charge the car at night and feed the excess solar to the grid?

Now obviously if this charger is only marginally more expensive than a normal 32A charger and you get 75% of the purchase and install price back in subsidies (UK), making if actually cheaper than a standard EVSE then why not?

Drive around on your day off and you'll see a lot of cars parked outside houses, not everybody works, and not all workers use the car to commute, and not all workers work during the day! A lot of folk do a morning school run, they may work from home and be in and out during the day and then are busy in evenings with school collections, going playing sports etc

I have two cars parked outside the house most of the day for example so this system would be of great interest (obviously I'd have to get an e.v too. The Tesla wall bank is great too but it's an extra cost so why not use the battery in your car in the same fashion

unkel

Tell me about it. I'm mostly working from home myself. My EV is charging on my drive right now

Still it makes no financial sense to install a PV array big enough to charge your house + your EV. As your EV can charge cheaply at night (and battery storage like the Tesla powerwall is prohibitively expensive). But as you rightly envisage, once you can use the massive battery in your EV as storage for your house (V2H), it will be a completely different ballgame. This is not yet possible though in a commercially available solution

Casati

unkel wrote: »

Tell me about it. I'm mostly working from home myself. My EV is charging on my drive right now

Still it makes no financial sense to install a PV array big enough to charge your house + your EV. As your EV can charge cheaply at night (and battery storage like the Tesla powerwall is prohibitively expensive). But as you rightly envisage, once you can use the massive battery in your EV as storage for your house (V2H), it will be a completely different ballgame. This is not yet possible though in a commercially available solution

I presume a fancy wall box charger will be coming along that will allow you to do just that, i.e. Draw from the car battery when it's not in use / not likely to be used

PV is a good idea on a new build as it a cheap way to satisfy the renewables requirements and this charger might help harness some benefit from it

unkel

There is some scope on ChaDeMo chargers to do this (you can find vids on youtube of people powering a party with a Leaf), but ChaDeMo is now obsolete. As in no future EVs will have ChaDeMo charging. And I don't think the CCS charging system (which is now the standard going forward) can handle control over the vehicle from the charger / two way charging. Not yet at least.

Very interesting vision of the near future though. Cheap near end of life second EVs and main EVs being charged up with home PV and / or ultra cheap night wind electricity and then feeding the house during the evening. Even with 50% EVs, we might not need substantially more capacity on the grid than we have now, with the right developments and the right subsidies.

KCross

unkel wrote: »

But as you rightly envisage, once you can use the massive battery in your EV as storage for your house (V2H), it will be a completely different ballgame. This is not yet possible though in a commercially available solution

Nissan have it commercially available. At least in Japan and I think they are making it available in Europe too. It was in a recent video I posted in the 2018 Leaf thread

unkel

Yeah I'm aware of the roots of the application after the earthquake in Japan in 2011 and all that. The 2018 Leaf is probably the last car ever to have ChaDeMo here, so going forward that's not much of a solution to most people.

BoatMad

KCross wrote: »

I still don’t see much benefit in this product unless you have an unusual profile where your EV charging is regularly done during the day, which must be a small minority?


Another issue…
@BoatMad, you’ve done some work on a load shedding EVSE.

Have you confirmed with the current Leaf that it can dynamically increase the Amps it pulls based on what the EVSE makes available?

e.g.
- Charge starts at 6A and everything running fine
- Sun comes out from behind the clouds and now Solar PV has 12A available and the EVSE makes that available
- Will the Leaf utilise the increased power or will it stay at 6A?

I vaguely remember you saying that the EVSE charge protocol doesnt allow for the EVSE to “tell” the car to increase. All it does is negotiate a starting current and then the car decides itself after that.

So, does (as opposed to can) the Leaf increase power drawn during a charge cycle if it becomes available?

My initial tests showed that a 2015 leaf seemed to only read the CP signal at the start of the charge and didn't respond dynamically.

Furthermore there is no way to pause the charging , on the leaf the Timer override would have to be retriggered to allow charging to restart

Unfortunately the spec for the CP wasnt written with dynamic charge currents in mind and there's seems to be no consistent approach to it.

KCross

Just wanted to give an update on the Zappi on the basis of some new features they've added which makes it more interesting to me now. I was dismissive of it up to now.

Its no longer just for maximising renewable energy.

They've also added load sharing and load shedding to ensure you don't blow the main ESB fuse. This is a brilliant feature that every charge point should be capable of, so that people can have two EV's in the one house.

So, the scenario would be:

- Your house has a 60A fuse (~14kW) in the meter. This is what most houses have.
- You have two EV's capable of 7kW charging each
- You have two 32A Zappi charge points so clearly running the two of them together at full load would blow the fuse.

If you have two Zappi's (with a Harvi monitoring the current at the meter) you can set the Zappi's to ensure that the incoming current for the entire house doesn't exceed, say 55A, and when it does (e.g. electric shower) the Zappi's will reduce their current draw to ensure it stays below 55A (or whatever you set).


Considering you would be charging at night you would have the majority of the 60A available and so would be able to get a combined ~12kW charge rate across the two cars and over the 9hr night rate that would be 100kWh+ per night on a standard domestic connection. Thats 700km+ per day across two cars.

You can buy the Zappi as a Type 1 or 2 tethered (5m or 8m) and they have an untethered version on the way.

The Tesla Wall Connector does this load sharing as well. It should be standard in all charge points. The Tesla is Type 2 tethered only though.
http://www.boards.ie/vbulletin/showpost.php?p=102576324&postcount=8

Shefwedfan

I was down with Electricautos this morning, they are up and running doing Zappi installations for anyone looking to install......

BoatMad

If you have two Zappi's (with a Harvi monitoring the current at the meter) you can set the Zappi's to ensure that the incoming current for the entire house doesn't exceed, say 55A, and when it does (e.g. electric shower) the Zappi's will reduce their current draw to ensure it stays below 55A (or whatever you set).

How does it " reduce " the current draw ??? , loads determine current draw

cros13

BoatMad wrote: »

How does it " reduce " the current draw ??? , loads determine current draw

I believe it's got a clamp meter with a small embedded system attached, 868Mhz wireless to the chargepoint which cuts power and sets J1772 PP-PE resistance for 32A, 20A, 13A or 6A or shuts off entirely as appropriate depending on the current limit set on the gateway.

BoatMad

cros13 wrote: »

I believe it's got a clamp meter with a small embedded system attached, 868Mhz wireless to the chargepoint which cuts power and sets J1772 PP-PE resistance for 32A, 20A, 13A or 6A or shuts off entirely as appropriate depending on the current limit set on the gateway.

many cars will not dynamically adjust charging rates dynamically , J1772 does not require it ( well its not mentioned )

The Leaf has certain issues for example , for example shut off ill will cause the timer override to fail and the car will not restart charging until the main timer kicks in

KCross

If it has to shut it off entirely then yes, the timer override would disallow it from restarting, if the timer is on.

It's a case of RTFM and understanding it and then adjust the timer to suit. It will have to adjust down a long way before it decides to entirely shutoff.

I obviously haven't tested it myself but I have asked them direct questions on it and they say it works.

I'll double check they tested with the Leaf as I see myself getting a load shedding/sharing EVSE in the not too distant future.

BoatMad

KCross wrote: »

If it has to shut it off entirely then yes, the timer override would disallow it from restarting, if the timer is on.

It's a case of RTFM and understanding it and then adjust the timer to suit. It will have to adjust down a long way before it decides to entirely shutoff.

I obviously haven't tested it myself but I have asked them direct questions on it and they say it works.

I'll double check they tested with the Leaf as I see myself getting a load shedding/sharing EVSE in the not too distant future.

do, because I have and the response of the car is not what you might expect , I do know that there have been software revisions in the car on this , so there is different behaviour across different model years

In my case , with a fairly early Leaf, the car seemed to sample the duty cycle on the control pilot only at the start of the charge cycle process.

KCross

BoatMad wrote: »

do, because I have and the response of the car is not what you might expect , I do know that there have been software revisions in the car on this , so there is different behaviour across different model years

In my case , with a fairly early Leaf, the car seemed to sample the duty cycle on the control pilot only at the start of the charge cycle process.

Their words....

All EVs on the market have to comply with the charging standards. They clearly say that the on-board charger has to adjust its power according to a change in the control signal (Control Pilot).

Basically, Zappi takes advantage of all the possibilities of the charging standard. Have a look on the J1772, you have lot of information on the net. According to this standard, all EVs have to respond within 5s. I can understand that you can be quite doubtfully on that, because it's the only charger on the marker that does that automatically !

During all Zappi R&D, we were using an Outlander PHEV and a 1st gen Nissan Leaf. We have tested Zappi on lots of cars (here at the office) (Zoé, Tesla, Volvo, i3,i8, Smart...) and according to customers feedback I can ensure that Zappi works well !

I asked him to clarify the reference to 1st Gen Leaf and whether he had tested later models....

"I've tested a 30kWh (6.6kW charger) Leaf for a month in Summer 2016. It worked even better than the 1st gen Leaf !"

Also bear in mind that the primary feature of the Zappi is that it tries to fully utilise Solar PV so it is continuously ramping up and down. That's its biggest selling point. This is a released product with real customers so I'd have to assume if that feature didn't work on the Leaf they would have heard about it by now.

Something is either different about your Leaf or they have figured out something in the spec that you haven't. They say its clearly stated in the spec, you say its not mentioned?!