Grid Interconnection, Inverters and Grid Codes
By Bjoern E. Christensen​​​​​​​
*Note: This blog was posted on LinkedIn on September 13, 2024

This is the fifth in a series of posts to build a bridge between the “expert V2G world” and the “non-V2G-expert world” and educate and address head-on the critical issues often raised with V2G.

Question: “Is the EV/EVSE pair interoperable with the electric grid?”

My last post focused on the interoperability between the EV and the EVSE using the same version of the ISO 15118-20 protocol.

To achieve interoperability between an EV/EVSE pair and the electric grid, we must also look at what it takes to be allowed to inject power into the grid.

In 2030, there will be millions of Distributed Energy Resources (DER) – EVs, Rooftop solar, Home batteries,..) connected to the grids. If these DERs act independently without living up to some pre-defined interconnection requirements, they risk making the whole grid unstable and unmanageable.

In short, the DERs must become certified “Good Citizens of the Grid” before being connected to the grid. The term: Good Citizens..” was coined by David Hochschild and Patricia Monahan, California Energy Commission. It is also known under the rather technical name of Interconnection Rule 21 in California.

For a DER (EV/EVSE pair) to be allowed to interconnect to the grid, it must support a set of technical requirements known as Grid Codes. An analogy is to think of an EVSE/EV pair needing a unique key to open the door (lock code) to the grid.

Most DERs, injecting power into the grid, are changing DC power into grid AC power.  This is done by power electronics known as Inverters.

So, fulfilling the requirements to interconnect to the grid mainly falls upon the Inverter, whether in the EVSE (DC) or the EV (AC). Therefore, California has defined a Common Smart Inverter Profile (CSIP) that DERs must support to be connected to the distribution grid.

Some examples of grid code support:

1.     If the grid frequency falls or rises for a shorter period due to a temporary disturbance.

The DER must not disconnect from the grid immediately since this could further aggravate the event. They are supposed to – for a given time – continue operating. This is known as Frequency-ride-through.

2.     The same applies to high/low voltage (Voltage-ride-through).

So, to be truly interoperable, the EV and the EVSE must:

A. Be able to talk and understand each other using the same protocol and
B. The EV/EVSE pair must be able to support the grid codes of the distribution grid.

This is precisely what the new International Energy Agency Task 53 aims to achieve worldwide (www.Task53.org) by gathering a consortium of EV/EVSE/DSOs/Aggregators that collectively support fully interoperable bidirectional charging solutions.

A follow-up post from @Marco Piffaretti will detail the first concrete step to ask experts for input on Gaps & Bugs in ISO15118-20 or Grid Codes hindering V2G interoperability.

Note: The 11kW inverter pictured is from Watt & Wells.

hashtag#Task53 hashtag#V2G hashtag#Bidirectional hashtag#IEA

CALL-TO-ACTION: V2G Standards and Interoperability​​​​​​​
*Note:  This blog was posted on LinkedIn on August 30, 2024

After a long summer pause, here we go again.

This is the fourth in a series of posts designed to build a bridge between the “expert V2G world” and the “non-V2G-expert world” and educate and address head-on the critical issues often raised in connection with V2G.

Question “Where are we on V2G Standards and Interoperability?”.

After many years of work, ISO 15118-20 (the EV-EVSE protocol) was finally released in April 2022. CharIN, which has hundreds of E-Mobility members worldwide, supports this protocol.

Note: Until ISO 15118 came along, the industry had been using the CHAdeMO protocol from Japan, which has been successfully used in many of the V2G projects over the last decade. But that is another story for another time.

ISO 15118-20 supports unidirectional and bidirectional charging.

So now it is plug-and-play time, i.e., each EV brand can communicate and understand each EVSE brand using the 15118 protocol!

Well, not so fast.

Different EV manufacturers support different protocol versions, e.g., ISO 15118-2 or the latest ISO 15118-20. The latter protocol is the only one that supports V2G, so the companies that support the 15118-2 protocol must “do some tricks” to support their version of V2G.

The net effect is a balkanization of V2G solutions like:

·       VW and E3DC
·       Volvo and DCBEL
·       BMW and Kostal
·       Honda and EVTEC

(European example)

Each solution pair works fine but uses “personalized versions” of the ISO15118 protocol. The solutions are NOT interoperable.

To scale V2G and reduce costs, we need to harmonize and make the V2G implementations interoperable!

Solving the interoperability issue will not remove all the barriers to scaling V2G (e.g. regulations, tariffs).

However, without V2G interoperability, we certainly will not be able to scale and reap the benefits of driving down the cost of V2G and creating meaningful, significant market penetration. What we did with the mobile phone is a good example of interoperability enabling a huge market penetration.

The International Energy Agency (IEA) has reacted to the call for action by creating a brand-new Task53 to facilitate Interoperability for Bidirectional Charging (www.Task53.org).

More on this in the next post.

hashtag#VW hashtag#BMW hashtag#Ford hashtag#GM hashtag#Stellantis hashtag#Honda hashtag#Kiahashtag#BlueBird hashtag#Siemens hashtag#ABB hashtag#Sch

Moving the V2G Needle – 
Enabling Bidirectional Electric Vehicle Interoperability​​​​​​​
*Note:  This blog was posted on LinkedIn on August 8, 2024

In 1997 Prof. Kempton, University of Delaware, published a paper titled “ELECTRICAL VEHICLES AS A NEW POWER SOURCE FOR ELECTRIC UTILITIES”. That was the start of the concept of bidirectional electric vehicles also known as V2G.

That is now 27 years ago!

Since, starting in 2011, more than 100+ V2G trials and projects have been conducted worldwide and important lessons have been learned (I have had the privilege of participating in 14 V2X projects worldwide since 2011).

The bidirectional EV supply chain has improved substantially and even Tesla has decided to come onboard with the Cybertruck.

California Public Utility Commission approved DC V2G in 2020 and we are also on the way towards approval of AC V2G

China announced its strategic interest in V2G last year with large field trials scheduled in 2025, and India has just completed a 2-year project – ‘V2X in India’.

And finally, after many years of work, the EV-EVSE protocol ISO 15118-20 international standard was released in April 2022

But still, V2G has not scaled in any meaningful way anywhere in the world

Just like the mobile phone industry experienced – what is needed to scale V2G is true seamless interoperability of V2G technologies from EV to EVSE to Grid Operator.

The new initiative from the International Energy Agency (IEA):
HEV Task 53: “Bidirectional Electric Vehicle Interoperability (INBID)”
sets out to facilitate this.  This task aims to test the conformance of the 15118-20 and upcoming amendments related to bidirectional charging

Task 53 has two main objectives to ensure interoperability between bidirectional:

1. Charging stations and vehicles
2. Charging stations and distribution grids

Task53 will work in harmony with existing international organizations and take full advantage of the many results already achieved.

Marco Piffaretti was instrumental in the creation of Task53 and Switzerland – as the proposing country – will cover a big portion of the organization’s cost. Website: https://task53.org.

I am proud and humbled to announce that I have joined the Task 53 team as a representative for North America. The team with Marco PiffarettiRegina Flury von ArxNicole Waechter, and I have close to 30 years of international V2G experience (https://lnkd.in/gM_J-zKb).

We will actively reach out to the V2G eco-system to recruit industrial members (EV and EVSE OEMs, Aggregators, Grid Operators, Universities, V2G Experts,… to join Task53.

I will present Task53 at the V2G Forum in Detroit, October 22 – 24, 2024, and be available for talks with organizations that would consider joining Task53.

We will be sharing more information on our efforts to move the needle on V2G interoperability on a worldwide basis. Stay tuned.

hashtag#V2G hashtag#interoperability hashtag#bidirectionalcharging hashtag#Task53 hashtag#INBIDhashtag#VGI hashtag#EVcharging hashtag#ISO15118
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