Open vs. Closed
Charging Stations:
Advantages and
Disadvantages
Open Standards –Based Networks White Papers
Open vs. Closed Charging Stations: Advantages and
Disadvantages
The transition to electried transportation is accelerating rapidly as electric vehicle
(EV) are expected to be more than half of new car sales and 33% of the global car
eet by 2040. As EVs are becoming more aordable and can go longer distances on a
single charge, more and more people are converting to electric cars. These trends are
augmented by recent announcements from countries around the globe to phase out
petrol and diesel cars. Countries such as China, the United Kingdom, France, Norway,
and the Netherlands have all announced plans to transition towards emission free
vehicles. To meet his growing demand for EVs, automakers are investing at least $90
billion in electric vehicles and will introduce new battery electric vehicles (BEV) and
plug-in hybrid electric vehicles (PHEV) over the next ve years.
2
With more EVs on the road, investments in EV charging infrastructure must take
place to reduce range anxiety and ensure that drivers have access to reliable charging
regardless of location and distance. This requires a multi-stakeholder approach to
planning and investment, one that encourages standardization and interoperability
of infrastructures.
Governments, utilities, automotive companies and corporations are at work planning
for this massive transformation in mobility. Decisions made today will have long-term
consequences for the future. Chief among those considerations is a need to facilitate
open and exible networks so drivers can easily charge regardless of network or
vehicle.
Car manufacturers have announced
signicant investments in
electrifying their line up and
allocating resources to R&D. This
growing demand for EVs is expected
to continue as analyst believe that
by 2040, 54% of new car sales and
33% of the global car eet will be
electric.
20 EV models
by 2023
12 new pure electric
vehicles to be launched
by 2022 and will invest
$1 billion into EVs
Invest to $11BN in EVs.
40 EV models
by 2022
Will introduce
only EVs
starting 2021
Electrify entire
lineup
by 2020
10 EV models
by early 2020s
Will invest $84BN in
R&D &
300 EV models
by early 2030
1
(Long-Term Electric Vehicle Outlook , 2017)
2
(Lienert, 2018)
Source: Bloomberg New Energy Finance, May 2018
2015 2040
55%
2020 2025
11%
2030 2035
Three types of charging station
networks
In addition to the three dierent charging levels, there
are three types of charging station networks being
developed to support electric vehicle (EV) charging: non-
networked, closed and open
Having a smart eV charging infrastructure that can
easily communicate with the power grid requires open
and interoperable communication protocols which can
support all the functionality needed by today’s advanced
charge management.
Closed networks
Closed networks use proprietary
communications protocols to
communicate between the charging
station and the network server.
Owners of charging stations must
use this proprietary network’s
services and compliant hardware.
They cannot switch networks using
the same charging equipment, and
they cannot use electric vehicle
supply equipment (EVSE) based on
open standards.
Open networks
Open networks use standard
communications to allow the
owners of compliant charging
stations to connect to multiple
open networks. Owners can run
dierent open standards–based
networking providers on the same
piece of hardware without the need
for signicant upgrades to existing
hardware.
Non-networked
These stations are not connected
to any network. Typically used in
residential applications.
Open vs. Closed Charging Stations: Advantages and Disadvantages
Today’s challenges in public EV
charging infrastructure
Much of the EV infrastructure that we know today has
been developed by private network operators that lacked
coordination and a shared vision of what a fully developed and
connected EV or optimally placed. This fragmented approach
has resulted in a market that requires EV drivers to have a
variety of memberships, accounts, and to RFID
cards to access
all publicly available chargers.
The lack of widely agreed upon standards for the backend
communication networks can also hinder the ability
to eectively integrate the charging stations into the
energy infrastructure and leverage the latest in grid-edge
technologies. To ensure a fully optimize EV infrastructure,
network operators will need to have the ability to integrate
charging stations into the power grid to enable additional
energy-related services. Interoperable and open networks
will allow data to be easily accessed, shared and collected
to improve charging services and plan for infrastructure
development.
What is OCPP?
Digital devices and systems communicate with each other to
get work done together. This back and forth communication
happens nearly instantaneously and seamlessly in the
background, allowing users to be productive without having
to think about the enabling technology. This is known as
interoperability, and it’s one of the fundamental building
blocks of our digital world. Interoperability is enabled by
communication standards known as protocols.
Open Charge Point Protocol (OCPP) is an internationally
recognized initiative with the purpose of creating an open
application protocol which allows EV charging stations and
central management system from dierent vendors to
communicate with each other.
OCPP acts as the intermediary between the charging station
and the backend or network management software. An EV
charging network is needed to allow network owners to
communicate with their EV charging stations and to allow
the EV charging stations to communicate with the power
grid. An advanced EV charging network will allow operators
obtain real-time information on the performance of their EV
charging stations, manage charging status, enable dynamic
pricing tools, process payments, and instantly detect faults
and issue tickets for servicing. The network management
software takes the information from the charging station
and communicates it to the back-oce server at a utility,
municipality or other administrator. On the consumer
side, this allows for services such as billing, access control,
authentication and payment. For the site host, it allows the
site host to set pricing and usage policies and to use data
to understand more about the behaviors and preferences
of charging customers. The charging stations needs to
communicate with the car, with the network operator, and with
the utility suppling power.
What are the advantages of proprietary
charging networks?
Proprietary networks allow the software developer or owner
to control all aspects of the charging ecosystem. This can
ensure a seamless experience for users. It is analogous to
the world of personal computing, for example, where Apple
maintains much tighter control over its operating system and
applications, but Microsoft Windows is licensed for use by
numerous manufacturers.
The downside to proprietary systems is vendor lock-in. An apt
analogy is between Android and Apple iOS devices. When you
have a device that runs on iOS, or charging hardware that runs
on a non-OCPP network management system, you are limited
to using that vendor’s hardware. Likewise, proprietary network
management systems only run on that vendor’s charging
infrastructure. If the network management system becomes
unavailable, it renders the charging stations useless, or at least
turns it into a non-networked station.
What are the advantages of open
standards–based charging networks?
The advantages of open standards –based charging networks
are exibility and choice. Open standards allow users to choose
many dierent hardware and network provider options. When
you install OCPP-compliant charging stations, you are free to
select the charging network provider that meets your needs.
Open systems oer the exibility to mix and match charging
hardware with the network management system on the
backend. When your needs change or you want to scale your
network, you can shop around for another OCPP-compliant
network provider if you want, or you can add charging stations
from dierent OCPP-compliant manufacturers. This allows
charging station owners to optimize the cost and risk of
networked infrastructure investments.
Open networks enable interoperability, allowing the
broadest possible set of products to work together. In
turn, interoperability promotes the expansion of existing
infrastructure. Open, universal standards make it easy
to introduce new hardware options that connect to the
existing network and are transparent to site hosts and EV
drivers. In a similar vein, utilities that invest in smart meter
infrastructure based on open standards are able to add smart
grid applications for outage management, demand response,
thermostat integration, street light integration and more.
The Open Charge Alliance has developed a hardware-
certication process to ensure seamless integration between
all OCPP-enabled devices and the back-end network
management system. Open standards vendors are investing
signicantly in building this technology.
Charging networks based on open communications standards
stimulate technical innovation by allowing free-market
competition to push down the costs of both charging station
hardware and back-end software, while dramatically lowering
the risks of hardware purchase for site hosts.
Beyond the benets to the individual charging station owner,
networks based on open standards represent the best path
forward to large-scale transportation electrication. Drivers
will certainly need more charging stations to relieve their
range anxiety. But as more electric vehicles hit the road, the
most practical and convenient approach will be charging
networks based on open standards.
EV drivers
Electric
vehicle
SAE J1 /
CHADEMO /
COMBO
Network
management
system
Roaming
access
Charging stations
Open Charge Point Protocol (OCPP) allows communication between charging stations and central system, regardless of vendors
OCPP
If your charging stations are OCPP compliant, you can easily
connect your charging stations to an OCPP-compliant back-end
network.
Shop around for
dierent hardware and
software options.
Mix and match
hardware and
software.
Easily add new options
and capabilities to
existing chargers.
The fast lane to
transportation
electrication at scale.
Benets of open
standards–based
charging
Flexibility
Scale
Plug and
play
Choice
Are non-OCPP networks truly open?
The short answer is no. Some charging companies claim to
use an open protocol because they have published their
application programming interface (API). Further, they claim
that their charging stations “speak” OCPP.
In many of these cases, the charging companies are still using a
closed, proprietary use a closed, proprietary protocol between
their back oce networks and charging stations. They build an
interface between their server and another OCPP-compliant
server, in eect translating between their proprietary protocol
and OCPP.
A closed network will not allow another network provider
to run organically on its hardware. Instead, it channels the
communications from the EVSE through their cloud to another
network’s cloud. This means that, even if a charging station
could run another back-end network service, the station owner
would need to pay for network services from both the original
service and the new service.
Only those charging stations with a native or organic
connection from the hardware to the back-oce network are
truly open. The station itself needs to speak in OCPP so that it
can talk with any OCPP-compliant server.
Background on Open Standards and
OCPP
The Open Charge Alliance (OCA) is a global consortium
of public and private EV infrastructure leaders that have
come together to promote open standards including OCPP
and the Open Smart
Charging Protocol (OSCP).
OCA provides open and
interoperable communication
protocols for EV charging
infrastructure to support
the functionality needed
by today’s advanced charge
management systems. Its
mission is to foster global
development, adoption and
compliance of communication protocols in the EV charging
infrastructure and related standards through collaboration,
education, testing and certication. Its membership includes
more than 50 participants spanning all sectors of the industry,
including charging equipment manufacturers, software and
systems providers, charging network operators and research
organizations.
OCA provides open
and interoperable
communication protocols
for EV charging
infrastructure to support
the functionality needed
by today’s advanced
charge management
systems
Countries that are currently using OCPP
OCPP is the de facto network protocol throughout Europe and is used in 78 countries
on every continent.
Open Standards and Grid Reliability
The growing adoption of EVs brings new and unprecedented challenges for electrical utilities and the power grid. As one of the
most complex energy loads to date, demand placed on the grid from EV charging is unpredictable and can spike at a moment’s
notice.
The clustering eect of
electric vehicles
As certain geographical areas provide additional support to
encourage the use of electric vehicles through incentives,
targets, or subsidies, that area may experience a clustering
of EVs within a neighborhood or community. The National
Renewable Energy Laboratory (NREL) recent report found that
clustering may “signicantly increase the peak demand seen by
distribution transformers and might require upgrades to the
electricity distribution infrastructure.”
3
However, coordinated EV
charging that is properly managed can help reduce the impacts
of EV clustering by prioritizing and scheduling charging during
o peak hours.
In order to safely integrate EV charging into the grid, electrical
utilities and EV charging stations need to be able to communicate
with each other. To facilitate this communication, a 130-member
consortium dedicated to open standards for the smart grid,
called OpenADR Alliance, have established a communications
protocol that standardizes messaging for price and reliability
signals used by utilities.
OpenADR is a global Smart Grid interoperability standard
developed to optimize electric supply and demand by
standardizing the interface between electricity markets and
end customers, and automating customer response to high
energy prices and grid instability. OpenADR 2.0 provides
secure two-way communications between DR servers, which
publish information, and the automated DR clients, which
subscribe to the information. Using OpenADR enables both
peak electric demand reduction and load shifting at client
locations according to customer needs and preferences by
continuously communicating dynamic price signals such as
hourly day-ahead or day-of real time pricing.
4
This is where OCPP compliant EV charging networks can help.
OCPP enabled charging stations allows network operators to
communicate with and control their charging stations. OCPP
allows for smart charging capabilities to throttle or post-pone
charging during grid events or moments when electricity prices
are high. Combining OCPP and OpenADR will transform EV
charging stations into exible grid resources that can instantly
respond to grid events and change behavior based on the local
grid requirements.
3
(Muratori 2018)
4
(OpenADR Alliance, 2018)
The growing adoption of EVs brings new and unprecedented challenges for electrical utilities and the power grid. As one of the
most complex energy loads to date, demand placed on the grid from EV charging is unpredictable and can spike at a moment’s
notice.
Typical load prole of a facility with EV charging stations
Time (Hours)
Power (kW)
To prevent overload of our current electrical power
infrastructure, energy demand from electric vehicle charging
needs to be managed
properly. There are several
ways to better mange EV
load by leverage Demand
Response (DR) techniques
or integrating local power
generation sources such
as solar, wind, or energy
storage. However, in order
to transform EV load into
a exible grid resource
that can participate in
utility-led DR programs or
communicate with the utility
to instantly respond to
changing grid conditions, the hardware and software needs
OCPP gives charging
station owners the
ability to not only
monitor the condition
of their charging
stations, but to
remotely authorize
usage. The most recent
version of the Open
Charge Point Protocol
is the OCPP 2.0
to function on open standard communication protocols to be
able to communicate with third party IT infrastructure. OCPP
gives charging station owners the ability to not only monitor
the condition of their charging stations, but to remotely
authorize usage. The most recent version of the Open Charge
Point Protocol is the OCPP 2.0 which allows for a controlled
charging process. This means that the EV charging station
and/or the central network system, can set constraints to
the amount of power that is delivered during a specic
charge. OCPP can be used at a local or global level to adjust
or limit the total amount power that may used by a group of
EV charging stations. OCPP can also be used to adjust the
power consumption of multiple stations to match the power
generation capacity of the grid. OCPP supports the Mode 3
PWM signal as well as more advanced smart charging such as
the ISO/IEC 15118 standard allowing for vehicle-to-charging
station/grid communication.
Facility Power (kW) Greenlots Managed Load (kW)
Peak Demand
Peak Demand
with Greenlots
Conclusion
As we transition away form internal combustion engine
to electric vehicles, adequate infrastructure that can
be responsive to the demands of drivers needs to be
put in place. In order for the charging infrastructure
to meet the demands of the market and consumers,
the adoption of open standards and interoperability
will be necessary. Open standards will not only allow
exibility with charging equipment, ensuring that the
EV charging networks stays up to date with the latest
About Greenlots
Greenlots is unlocking the possibilities of the new electric mobility future by
delivering innovative software and services that empowers utilities, cities,
communities and automakers to deploy EV charging infrastructure at scale. Our
technology is connecting people to their destinations in a safer, cleaner, and
smarter way. Headquartered in Los Angeles, CA, the company’s global footprint
spans across three continents with deployments in 13 dierent countries.
For more information contact us at
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technology, but will also allow for open communications
between the driver, the vehicle, the charging station
and the grid. An open network would facilitate dynamic
load management that can synch with the grid operator
pricing signals, integration of renewables, easy exchange
of vehicle information and streamline payment and other
transactions. Ultimately, open standards would allow for
an EV charging infrastructure that is accessible, more
reliable that enables an enhanced driver experience.
The Open Charge Point Protocol Roadmap
OCPP 1.5 released in 2013 OCPP 1.6 released in 2015 OCPP 2.0 released in 2018
OCPP 1.5 is a SOAP over HTTP based
protocol for operating a Charge Point from
a Central System. This allows data to be
exchanged from both charge point to the
central system over the internet. OCPP 1.5
supports the following key functionalities:
Charging station is able to make contact
with the central system upon startup
Authorizes the start and stop of charging
sessions
When a rmware update is ready the
central system will send a message to the
charge point
Communicates technical errors or failures
to central system
The central system can ask a charge point
to send diagnostic data
There is the option of reserving a charge
point
Change Conguration enables a central
system to modify dierent charge point
settings
OCPP 1.6 introduces new features to
accommodate the market: Smart Charging,
OCPP using JSON over WebSocket’s, better
diagnostics possibilities (Reason), more
Charge Point Statuses and TriggerMessage:
Support OCPP 1.5 functionality
Firmware Management (updates and
diagnostic log)
Local Authorization list management -
manages the local authorization list in the
charge points
Supports the reservation of a charge point
The TriggerMessage message is added,
giving the Central System the possibility to
request information from the Charge Point
Smart Charging - allowing the central
system to inuence the charging power
or current of a specic EV, or the total
allowed energy consumption on an entire
charge point
OCPP 2.0 introduces new features to
accommodate the market; mainly to improve
handling large amounts of transactions,
increase cyber security, extend smart
charging functionality, and to include Plug &
Charge ISO standards. New features include:
Extended security (i.e. security proles,
certicate handling, encryption, security
logging, etc.)
Device Management of the Charge Point
for improved provisioning, monitoring and
maintenance. This also allows a Charge
Point Operator to monitor, congure
alarms etc. on a lot of parameters in a
Charge Point
Improved Smart Charging support
including:
Vehicle to grid
External local smart charging signals
(HEMS)
Support for ISO/IEC 15118 including
Plug-and-Charge
Support for displaying taris & costs
