no worries, that what i notice about this forum it not really geared toward energy saving or even reducing demand and/or resources so much, which is fine. my goals are different then most . . and electric car with a 100 - 400 km (15 - 100 kwh) of stored energy potential while the average user only uses 60 km ( 9kwh) - so one can shift daily over production to nightly consumption… a smart house/grid that relatively self contained using the least resources. ie 8-9 months out of the year using very little energy from the grid.( as I live very harsh environment compared to most on this forum.). – okay sorry for hijacking your thread a bit your input was appreciated…
Well that depends on your personal situation. I believe most of us are working with the car at the office when the sun is shining at home. Where do you store the energy then? And when you arrive home at night with the car depleted where is the excess that you can use at home? And on a sunny weekend will you go with your EV and your family somewhere or you will force yourself at home to harvest some more energy?
My opinion is that it doesn’t make sense to buy a car to store PV energy today, i as a owner cry for more range in my car to get rid of my ICE vehicle. And if you are really into energy saving, you know that it is most important to switch from ICE to EV than to fine tune inefficiencies in the charging process.
well for me my personal situation. I work from home. so generally my car is at home anyway +5 days out of the week , secondly i already have storage bank. as in a small electric utility .and small stand alone set to handle when I am away with the car . thirdly and most importantly for energy security. as I said i live fairly harsh environment. and after particular brutal storms ie ice storm , torrential rain , blizzards or other major weather events-- as they are happen more and more frequently due to the effects of climate change ( currently yearly almost) . the power has being out for several days, not personally for me but for some of my neighbours for weeks. in the summer it not bad but in the winter at -30c that’s life threatening . the cost advantage to buying a battery set in preparation of an even that only currently happens “rarely” makes no sense.So using existing resources is more prudent . also currently my power company does not have smart meter that uses time of day tariffs. but they are slowly moving to that system i would say with in 5 years . and in that case what i am doing now become extremely advantageous in the near future -
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also then by your own statement what the point of your project or any project related to emon and electric car charging /diverting as your cars rarely home to take advantage of it ???
by the way when i can pick up a used Nissan leaf for less then 10,000 CAD with less then 30,000 km that 24 kwh of potential power it is a lot cheaper then buying a stand alone lithium battery pack of the same size
Well if you read carefully the discussion in this topic you will find that my goal is to minimize contracted power and maximizing charging power. Today i can’t live without it, i just plug the cord and forget. The car will be charged as fast as possible and i won’t have to compromise the utilization of energy at home.
Other have different goals or will do things in a different way. You asked for my opinion you got it. We disagree, thats fine.
as i said no worries, we have the same end goals just different ways of achieving it.you want to maximize the charging of your EV I am looking at maximizing my solar production and energy security okay again sorry for hijacking your thread - have a good day…
Nice work, the graph speaks for itself. Very impressive. I hope to do the same thing using openEVSE.
So far I’ve successfully been able to vary the charge rate of the openEVSE using RAPI commands:
I’ve just been reading up on the charging efficiency of charging a Nissan LEAF. It seems the charging is more efficient at higher currents.
Here is the full report
Interesting to know, so when reducing the charge rate when diverting from solar maybe it would be best to have a 2Kw cut off?
Please take in account the North American Standard, these tests are made at different frequency and voltage. The chargers for European market operate at different settings and that can have impact on the tests.
Practically all chargers are terrible at low voltage & low amperages. In Portugal and UK the minimum would be 230V / 240V at 6A that scores a efficiency above 80% and that’s fine for diverting in my opinion.
Also L1 and L2 are mutually exclusive, so a cutoff would has no effect, i think!
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Just seen on Indiegogo there is a company crowdfunding a solar PV charge diversion controller. Looks nice, I like how they have defined three modes of operation:
This is possible using openEVSE at the moment. I’m working to try and make it easier. It would be nice to have an EV specific Emoncms dashboard to show in real-time who much power is being diverted from solar.
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A custom dashboard would be awesome! And if you could integrate periodic feedback from carwings with the 12 SOC bars would be crazy cool!
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I’ve just started a new thread to document my current progress using NodeRED and MQTT to control OpenEVSE charge rate based on solar PV production:
Hi All,
Our Charger uses Open Charge Point Protocol (OCPP) version 1.5 over JSON, do you think this could be intergraded in to the system?
Thanks
Paul
Hi Paul,
I’ve never heard of this OCPP Protocol, can you elaborate more on this?
Regards,
Sorry Paul, you need to do better than that!
GitHub - NewMotion/ocpp: Open Charge Point Protocol perhaps that help you along it also point to other references
I’m sorry i’m not the one that needs help lol
I’ve been reading about OCPP - thanks paul for that, i had no idea what it was - and it is not Open like Openenergymonitor, it’s open for the companies that what to be part of it.
I found no server, and no implementation ready to test, it’s all about the possible messages that a unknown central server makes to the charging station. Actually V1.6 can also change pilot signals, however only V2.0 (draft) brings full encryption and that seem really late.
- For a personal charging station it’s completely overkill and useless.
- For a commercial project it’s perfect
- For a community driven charge infrastructure would be interesting ( but probabily illegal in most contries)
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Using a Solar Cell to Control an EVSE (via the EPC)
Hi All,
I have not read all the way through this thread so forgive me if the subject of this post has already been mentioned or is not relevant.
People trying to match their EV charging current to their PV output (to minimise exported energy) may wish to consider using a small solar cell in proximity to the EVSE with a reasonably clear view of the sky. On the basis that the solar cell will be illuminated in approximate proportion to the PV array and at the same time (roughly), this may be a lot easier to implement than other methods especially when the EVSE is remote from the PV and/or its control electronics (ie a clamp-on inductive-type sensor is inappropriate/too expensive).
It would certainly be a useful addition to what has already been submitted here if one were interested in using the Viridian (Mainpine) EPC which I sell through my webshop at EVBitz.uk (related plug so I hope it doesn’t upset the moderators).
Regards, Martin Winlow.
Director EVBitz.uk
Hi,
I understand your point, however in my opinion the best way is to have a remotely controlable EVSE, like the one i’m developing here (EVSE Colaborativo - Clubeletricos.com).
With this EVSE, the integration is direct, since it talks the same language as the IoT platforms like Node-RED. To make everything work we just need a bidirectional energy sensor and a raspberry pi ( a emonPi) and we’re set.
There are other EVSE that can change Amps, instead of adapting a solar cell to change the current based on the intensity, maybe it’s easier to adapt a ESP8266 to control the amps and provide remote control via WiFi. OpenEVSE is a great example of this approach. It should’t be hard to integrate ESP8266 with the Viridian EVSE.
This only works if you can assume that all the solar is there to be diverted. In my set-up I am only diverting - or trying to - the spare solar that is not already being used in the house, i.e. what I would otherwise export.