OCPP 1.6 and OCPP 2.0 – which one is better for you?

OCPP is an open protocol for communication between Charge Points and a Central System that quickly became the industry standard. It is a universal solution accommodating any type of charging technique. Since its release in 2015 OCPP 1.6 was downloaded tens of thousands of times and its successor followed in its footsteps. OCPP 2.0 launched in April 2018 was implemented by thousands of users and its popularity is still growing.

Open Charge Point Protocol powers EV charging stations

OCPP stands for Open Charge Point Protocol and it is created by the Open Charge Alliance (OCA) in 2009. Today global consortium that promotes open standards has more than 220 participants from 43 countries on 5 continents. OCPP became the EV industry standard in just 6 years.

The Open Charge Point Protocol allows communication and data exchanges between electric vehicle charging points and central control systems.

As for now, most of the modern  EV chargers are OCPP 1.6 compatible, with the raising amount of station manufacturers delivering hardware ready for OCPP 2.0.1 in order to anticipate future requirements of the e-mobility market and to prevent the money loss caused by stranded assets. That’s one of the reasons why the majority of implementations are still based on OCPP 1.6.

Open Charge Point Protocol (OCPP) 1.6. - what made it revolutionary?

Open Charge Point Protocol OCPP 1.6 was the first OCA protocol to gain world wide recognition. It’s perceived as the all-in-one solution that to this day isn’t lacking anything important despite the huge technological progress that the EV industry made.

The feature launched within OCPP 1.6. that reshaped the perception of EV charging was smart charging. It allowed sending  Charging Profiles to the charging station – basically a foundation of today’s EV charging infrastructure. Central System gains the ability to influence the charging power or current of a specific EV, or energy consumption on an entire Charger / Charge Points network.

Smart Charging has three typical use cases:

load balancing

central smart charging

local smart charging

 

LOAD BALANCING

OCPP allows the management of internal load balancing within the Charge Point that modulates the charging schedule per connector. Every Charger is preconfigured with a fixed limit, mostly the maximum current of the connection thus it allows to get the most from the deal with the power distributor without the risk of an outage. CPO has the option to set up a minChargingRate that may be used to optimize energy distribution between the connectors. Clients wouldn’t be able to charge in an inefficient way and will be automatically redirected to other services based on a fitting balancing strategy.

CENTRAL SMART CHARGING

Central smart charging enables Central System to regulate the charging schedule, per transaction. Schedules allow staying within energy usage limits imposed by any external software on the entire network by controlling each Charger.

LOCAL SMART CHARGING

Charging limits on Chargers are controlled by the Local Controller instead of the Central System. This use case of smart charging describes limiting the amount of energy that can be used by a group of Charge Points (small network like a parking garage), to a given maximum. Another scenario would be receiving information by the Local Controller about the availability of power from a DSO or a local smart grid node.

WHAT WAS INTRODUCED IN OCPP 1.6?

Switch to JSON over WebSocket , reducing data usage and enabling OCPP communication through NAT routers.

Extra statuses, giving the CPO and EV drivers more information about the current status of charging.

Extra values are added, which creates the possibility to send new information to a Central System.

The TriggerMessage message is implemented, introducing the Central System to request information from the Charge Point.

Other functionalities making the implementation of the OCPP clearer, easier and available in steps.

OCPP 1.6 vs OCPP 2.0

The easiest comparison of the two versions would be as follows: OCPP 1.6 is a very good, well-understood solution that is sufficent for today’s usecases.. The OCPP 2.0.1 is the protocol of the future and as such, its adoption is slow.

Open Charge Point Protocol OCPP it’s now available in version 2.0.1 that incorporates improvements for inconveniences found in OCPP 2.0 during Plugfests and in the field. It’s a minor change, not introducing new features or functionalities. Updates have been made in the area of security, ISO 15118, Smart Charging and the extensibility of OCPP.

V2G Technology

The concept of V2G technology was introduced by Kempton and Letendre in 1997. In a typical power grid, the power flows between energy producers through the power network to aggregators and homes. In the homes, power outlets provide energy to products such as electric vehicles. By default, the EVs should be able to connect to the grids to recharge their batteries. An electric vehicle that incorporates V2G technology can also provide energy back to the power outlet when the vehicle is parked. The EVs require additional setup to successfully return the power to the grid to perform this type of bidirectional charging.

Implementing a V2G architecture could potentially decrease the stability of the power grid. However, aggregators employ dispatch and control algorithms to optimize that stability and balance the energy distribution to the EVs. In that way, a vehicle can ultimately charge during the times when energy demand is low and discharge when it is high. However, the potential effect that this may have on the stability of the power grid has not  been studied sufficiently. Furthermore, the data that is collected can be susceptible to security issues, and privacy concerns among consumers might arise . Ideally, these challenges will be addressed before the technology becomes adopted on a large scale.

The benefits of V2G technology are technical, economic, and environmental in nature. First, the grid’s power storage capacity will increase gradually with the increase in the number of EVs sharing the power with the grid, allowing more power storage in the grid. Second, the transition to V2G technology can replace 6.5 million barrels of oil usage per day, and it directly amounts to economic savings in a country . Third, the transition can reduce greenhouse gases emitted by gasoline-based vehicles and promote EVs’ usage in society.

The V2G systems need communication protocols to enable the transmission of instructions between the EVs and the electric vehicle supply equipment (EVSE). When the communication chips and protocols are in place to receive the signals, the aggregator can coordinate between the EVs and the electricity grid operator to regulate power supply and demand. The communication protocols related to EVs are divided into front-end and backend protocols. 

The front-end protocols define the link between the EVs and EVSEs, and also specify the requirements related to charging topologies (such as type of charging equipment (on-board/off-board) and type of charging (conductive/inductive), safety, charging plugs, communication, and cybersecurity. A few examples of front-end protocols include IEC 61851, ISO 15118, SAE J2847, and CHAdeMO. 

The back-end protocols define links between the EVs and third-party operators such as charge point operators (CPOs) (companies responsible for operating a pool of charging points ), and specify requirements related to communication and cybersecurity . A few examples of back-end protocols include the open charge point protocol (OCPP), IEC 63110, the open automated demand response (ADR), and EEBUS. More information on these standards can be found in .To technically realize the V2G system, a simple communication chip is added to the onboard charger of the EVs to regulate the power flow between the EVs and the grid.

However, designing this communication technology is expensive. Therefore, most EVs are not equipped with these chips today, except for a few EVs manufactured by companies such as Nissan and Mitsubishi. Besides, energy meters capable of measuring the power flow between the grid and EVs accurately are required. For monitoring the real-time power flow, advanced metering infrastructure (AMI) is used to provide reliable information to aggregators and grid operators for managing the power flow in and out of the grid . Currently, one technology, CHAdeMO, already offers V2G technology, while another technology, CCS Combo, is expected to offer V2G technology in the future.