V2G/H and EV and on grid.

[brackwell]

So bearing in mind i am on grid with a EV and want to use the EV (Peugeot Ion with 16kwh batts) in V2H scenario.  What do i do then?  Realise i need a inverter but of what capacity but more importantly how do i control the output so that it matches the requirements of the house and does not just send it down the grid ?

We have to imagine the car may one minute being charged with PV and then a load goes on in the house so is now discharging by just the amount necessary and then vice versa.

I do not understand why this has not been commercialiased and become a off the shelf system.  This is like the days of the first PV diverters and is just now waiting for initiative.  I am not capable of waiting much longer and so DIY here we come with the help of semi off griders on here.

Ken

[Tinbum]

I do not understand why this has not been commercialiased and become a off the shelf system.Ken

I think it has. I think they have it in Japan.

[M]

I assume what you are looking for is the technology used to manage a domestic battery system. It would have to monitor leccy flow, diverting to car when it detects export, or diverting from the car when it detects import. So, does the control kit for the many domestic batt offerings exist as a standalone purchase?

Alternatively, how about two EV's one for use, and one for charging, perhaps a bike?

Electric Motorcycle Doubles As Residential Storage Battery

[TheFairway]

The potential impact of this technology and other beside is already being assessed. http://www.electricnation.org.uk/about/technical/

[Tinbum]

http://www.nissan-global.com/EN/TECHNOLOGY/OVERVIEW/vehicle_to_home.html

[brackwell]

They have been talking,evaluating blah blah for nearly as long as i can remember. Mitsubishi and Nissan in Japan both introduced low capacity 110V outlets to their cars, and hence the reason the Outlander has a fast charger, but now it has all gone quite.  There are a number of systems on test around the world but none will be viable at domestic level.  At this moment in time nothing exists.

So we need to start by thinking of the EV as just a bank of batteries on a shelf in the garage and then what do we do. Come on you off gridder types you are already doing most of this already.

Tinbum -i think that ref is old which goes to prove my point.

Ken

[TheFairway]

One EV with a 16kW battery does not scale up very well at a national level. Don't blame them for wanting to assess the potential impact on the whole grid over a very real set of timeframes in time prior to large scale EV adoption potentially triggering unmanagable scenarios. The alternative is blanket restrictions like we have with export limits which isnt going to do anyone anygood.

[billi]

not sure if i now talk technical bullsh/te ,   perhaps i go and think about it,  after  writing here ....

Upfront (i did think about it  a good while back)   ... unfortunately most  el. vehicles ,  are not plugged in, while the sun is shining  , so i thought   a fully charged  during the day second battery at home ,  would be an idea   , or  a battery at home supplying the house needs and as well charge the EV battery at night , or vice versa would make sense

I estimate the battery voltage of the " Peugeot Ion with 16kwh batts"  at about 350 volt  , so  an Hybrid -Inverter with high voltage input  Mppt charger  springs to my mind

, i guess it can be feed by a high voltage PV string or  as well  just connected to the car battery to feed the house with  a  device  like this

 http://www.ebay.de/itm/PV-Wechselrichter-Hybrid-4000w-mppt-48v-PV-energiespeicher-netzunabhangiger-/162320344713?hash=item25cb0be689

  

Hybrid SOLAR inverter with 3 operation modes: Grid-Tie, Off-Grid, and Grid-tie with battery backup
• Pure sine wave output with max 4kw continuous output
• MPPT tracking with PV support up to 5000w!
• Max PV input 580Vdc

• Dual AC input: generator + grid

• EMS port - emergency load

• Stackable up to 6 units!

• Built-in 80A battery charger
• Supports both 50hz or 60hz (program adjustable)

• High efficiency transformerless design
• Large LCD display of comprehensive system info
• Max Grid-Tie conversion efficiency up to 96%!
• Peak inverter efficiency 93%
• RS232 and USB interface available
• User programmable functions
• Bundled monitoring software with setting programs
• Energy Saving
• Certified in Germany standards VDE

• Certified in general EU standards CE

so  the car battery could be attached to that devices mppt charger at night    and the Inverter thinks it is a  PV   and the EV battery  is just  drained  as much as the house needs  
In addition  a small 48 volt  house battery is needed,   to activate run that inverter   , that then means  that the home PV is  running the house , during the day  through this hybrid inverter  and  as well optimizes the own self consumption , as well feeds the grid   ......

How easy that is  to switch over  every night  to  an offgrid scenario (inverter programing  or just cut off the national grid via switch ? to avoid  feeding  the grid with the EV battery) and to  change the  + and- from the PV to the car battery ...  

have to think  more ...

Billi

[rogeriko]

all the manufacturers have different chargers there are no standards. there are several people making home made chargers for their  pv systems google is your friend. There is a lot of money to be made but dont forget the standard 3.8kw will not do anything most of the year you need at least 10kw of panels to even think about charging your car.

[brackwell]

Please do not make such sweeping statements. There are so many different lifestyles,car usage patterns,total mls/yr,types of EVs etc.  In any case you may have misinterpreted the question due to my lack of background info.

The objective is not to supply ALL my EV leccy from the PV but to use as much of my present PV as possible to charge the EV and then to use that as back up to the house where and if possible ala Powerwall. Over the yr my PV production is equal to house+DHW+EV charging but of course time wise the production and usage do not align so the more i can bring these in to alignment the better.

Further, one Kw of PV used in the EV is worth 40p+ in displaced FF ( + CO2 )..  Forget heating DHW and start charging EVs. It also makes FITS rates irrelevant !!

Ken

[charlieb]

Further, one Kw of PV used in the EV is worth 40p+ in displaced FF ( + CO2 )..  Forget heating DHW and start charging EVs. It also makes FITS rates irrelevant !!
Ken

I was just about to do my standard thing of asking why you'd bother, but you more-or-less answered it there.  (I think the satisfaction might actually be more important right?)

As you say Ken, they've been talking about V2G for years but not doing much. I think that the scenarios that will come to market quickest aren't about a 10p/40p+ differential but rather about the demand-spikes that are really causing problems - ie the few winter evenings when Triads and Capacity payments etc are all in place and the effective price of an extra kWh is up to many £/kWh. (Although not to a home owner.)     I see a big role for EVs in this - solving real problems on the grid - once the aggregators are engaged and smart-meters mean there's real evidence.   Doing it for just PV self-consumption will stay a niche imho.

(I kind of hope I'm wrong.  EV's used for PV self-consumption don't really impact on the need for grid-scale Energy Storage;  if they're used for reducing grid peaks, though, they'd compete directly with our technology and almost certainly be much cheaper!)     

[ringi]

There are standards for chargers letting the chargers control how much power the car takes while charging.   How well the cars can control the charging power down to the level of your PV output is a different question.....

I have seen BMW claim that with there expensive charger you can control a i3 so it charges from your PV.   However it would take money years to recover the cost of their charger....

You could do worse then having a mains switch that turn on the power to your charger whenever you were exporting more then 2kw, and kept it turned on for the next 15 minutes.

[brackwell]

Your 2Kw/15 mins proposal is exactly what i envisaged although i might change that to say 1.25Kw for Dec and Jan  Although one needs a manual switch for just in case.

A EV can be charged at different preset, not variable, levels down to 6amps i believe but anything below the 10amp home charging lead must be a bit problematic.

Charlieb,  You bet its about satisfaction as there are easier ways of making/saving money.  If one believes in clean transport then this kind of thinking ,but not necessary this solution, is a game changer.

Ken

[ringi]

What you really need a system when you tell the car how much range you need and when, the car then charges itself whenever there is PV output, then charges on E7 or full price if required.     Apart from software in the car, it would only take a sensor on your main cable, so the car knows when the PV was exporting.
The water heater PV diverters would than need a delay before it started, so that the car got first option on excess PV power.

(Note that there is no need for the socket you plug the car into to have any "smarts"....)

[brackwell]

ringi,
The, charging the EV bit,  is already sorted by using a Immersun diverter (guess there are others).   

 At the beginning of the day initially excess is used on the DHW until the 2Kw PV level is reached when a relay switches on the EV charger and switches off the DHW and then vice versa in the evening.  There remains a question of what to do with further excess in the summer day.

While the above is taking place the EV wants to supply peaking demand like the kettle,heater on the dishwasher and washing Mc for eg.

Under certain circumstances the EV can supply evening demand but this is where it gets a bit tricky because the EV may need to be charged for the next day, or not.  Also dont want it to be fully charged as next day there will be nowhere for the PV to go.  I actually do not have any figs for what my house may consume in a evening.

Of course there are times when the EV is not available but this probably coincides with minimal house demand and perhaps there is still some capacity in the DHW.

Those with a 9 to 5 living would best incorporate E7

Ken