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Distribution grid planning and operational principles for EV mass roll-out while enabling DER integration

Final Report Summary - PLANGRIDEV (Distribution grid planning and operational principles for EV mass roll-out while enabling DER integration)

Executive Summary:
The mass roll-out of electro-mobility, in conjunction with the increased production of electricity derived from renewable sources, is one of the major opportunities to reduce CO2 over the next decade. The efficiency of electric engines is superior to that of combustion engines and the renewable energy sources used to power them are naturally CO2-free. Additionally, the fact that electric cars use batteries takes care of the issue of energy storage, helping to overcome the problem of renewable sources only being available when the sun is shining or the wind is blowing. The battery in the car, in combination with an energy management system that can monitor the availability of renewable energy, is a major opportunity.

The challenge of these two growing movements is the requirement for large scale interaction between energy supply and demand. While this is a well-known balance in need of management in industrial production plants, it has never been applied at grid level. Moreover, the fact that the controlled loads (electric vehicles (EVs) in this case) are moving around and are only connected to the grid from time to time has never previously been taken into account. To date, there have been no grid planning tools designed to meet these opportunities and challenges.

The new hurdle for grid planning is that although the grid extension needed to provide the energy for EVs is actually rather small, the power need, especially for fast charging, is substantial. In the end, it’s not only the delivery of the energy that is the problem but the power itself. The delivery of the power might depend on the charge scheme in use: fast versus grid-friendly. Challenges arising from this are line loading issues and voltage as well as the necessary introduction of ICT in the low voltage (LV) and medium voltage (MV) grids.

To overcome these challenges, the EC funded project ‘PlanGridEV’ has developed a totally new planning approach for distribution grids, implemented in a prototype tool. Instead of simply considering the estimated peak load of the grid, as with traditional distribution grid planning, the PlanGridEV approach additionally considers the controllability of the loads in conjunction with the estimated generation from renewable sources. PlanGridEV synthetic models for the major components of car movement and charging, wind generation, PV generation and storage have been developed and integrated. The new planning tool takes into account not only one peak load day but stochastic behaviour over a several month planning horizon. Additionally, an ICT communication model has been developed and integrated to derive the necessary ICT components for a certain implementation.

Based on a set of scenarios and use cases calculations have been performed that prove that there are major benefits with the smart grid approach. Depending on the set-up, the peak load could be reduced by half compared to an uncontrolled charging scenario. Furthermore, the usage of renewable energy could be increased without interfering with transportation needs. This clearly shows that in an all-electric world the smart grid approach will play a major role.

Finally, PlanGridEV has been able to show by using the prototype tool, that a new grid planning approach is feasible and leads to the desired results. It could be proved in the simulations and in the test beds that the new approach leads to less expensive grids while providing all the energy the customer needs. In conclusion, we have found a way in which a full roll-out of electric vehicles is feasible. The implementation requires that regulation and the market develop accordingly, with respect to the new functionality that will be available in the coming years.

Project Context and Objectives:
It is estimated that by 2025, about five million electric vehicles will be on the road all over the world, the majority of these in the EU. European climate policies aim to significantly reduce CO²-emissions from transport by 60 % by 2050 and to reduce the use of “conventionally-fuelled” vehicles in urban transport by 50 %. With technological advances and new mobility concepts, as well as a steadily rising oil price, it can be assumed that electromobility in Europe will increase. Simultaneously, the feed-in from DER is also expected to dramatically increase in order to meet the goals of EU and national climate protection policy. Therefore it can be expected that distribution grids will need to significantly increase their hosting capacity to accommodate fluctuating supply and mobile loads, in such as EVs.
Large-scale EV introduction will moreover only be successful if the expectations of customers are met and current constraints are overcome. This requires further technological development and the intense cooperation of all stakeholders, including OEMs, DSOs and energy service providers, for example in operating a sufficient (fast) charging in network infrastructure.
The main objective of PlanGridEV is to design new planning rules and operational principles for the optimal integration of electric vehicles (EVs) for different network topologies and with different levels of distributed energy resource (DER) penetration such as photovoltaics (PV), wind and solar energy and micro combined heat and power generators (CHP).
It aims to identify the key features that future network planning tools should incorporate in order to allow for an adequate assessment of EV demand. It acknowledges an environment characterised by increased uncertainty, but also by greatly improved network management capabilities at the distribution network level. Tools and methods have been developed that permit Distribution System Operators (DSO) to design new or adapt existing planning rules and investment strategies to ensure technical efficiency and the cost-effective evolution of infrastructures to facilitate the mass roll-out of EVs in networks characterised by different levels of DER penetration. Finally, recommendations for regulatory frameworks and further developed business models are presented.
The overall objective can be broken down into the following five sub-objectives:

1. Development of tools and methods to design new planning rules involving DSOs/OEMs
Based on a comparative technology and regulatory gap analysis including an assessment of stakeholder needs, methods and tools have been developed to design new planning rules to manage controllable loads, integrate distributed generation and exploit storage options.
2. Development of new planning rules for European DSOs to facilitate the mass roll-out of EVs whilst enabling DER integration
European DSOs are enabled to develop new planning rules to optimize grid planning taking into account the stochastic nature of renewable energy sources and EVs and maximising DER hosting capacities of the distribution network.
3. Updating and validating of operational methods addressing load congestion issues at local level
Methods for network operation are updated, tested and validated in existing EV test beds to address local load and congestion issues.
4. Deriving and updating of investment strategies considering new business models of DSOs and OEMs
Existing DSO investment strategies are updated to enable the creation of investment roadmaps for different scenarios of EV and DER integration taking into account new methodologies for network planning that have been developed in the course of the project. The investment strategies consider different business models and regulatory enhancements needed to support DER integration.
5. Formulation of recommendations regarding the regulatory framework and standardisation efforts
Building on the previous results and the newly outlined planning rules, recommendations for the contribution to on-going standardisation efforts as well as regulatory initiatives are derived.

Project Results:
See pages 20 - 59 of attached publishable summary.

Potential Impact:
In PlanGridEV, for the first time an evaluation of the benefits of Electric Vehicle (EV) smart /controlled charging in conjunction with renewable generation has been carried out. The need for smart charging was addressed already in 2014 by the European Alternative Fuels Infrastructure Directive 94/2014. Which has to be implemented in the member states by the end of 2016. According to the results of the studies carried out in PlanGridEV there are several points that need to be established to create a framework based on the directive that paves the way to a mass-rollout of e-Mobility.

The major finding is that smart charging is the only way for a mass-rollout of e-Mobility avoiding massive costs to reinforce the grids.

The PlanGridEV results prove that the additional energy needed to supply the EVs can be easily provided by the existing energy system while the power demand of uncontrolled charging would result in massive grid investments.

A similar effect of a negative impact due to missing control mechanisms has been recognized with the mass integration of photovoltaics (PV) in the German grid. Control of PV generation has not been taken into account in the beginning and this has been resulted in major grid investments. Finally a directive was enacted that peak generation curtailment and control mechanisms have to be implemented also in existing DER systems.

In the Italian test bed different scenarios with and without EV and PV penetration in different charging schemes has been tested. As a result it’s clearly observed that a controlled conjunction of DER generation and charging EVs is able to lower the saturation of the LV grids which will lead to lower grid reinforcements. The tests in the Italian test bed showed that in this case the modulation hours can be reduced and the PV penetration can be increased.

To establish the framework two things are necessary.
1. The proposed architecture needs to be available.
2. A market model needs to be established that enables smart charging business.

PlanGridEV has proven that the technology to build the proposed framework is available at a technology readiness level (TRL) of 6 which means that the proposed control schemes could be verified within the test beds of the four participating Distribution System Operators (DSOs). Additionally laboratory tests were done showing that all the EVs on the market are generally able to fulfil the needs of the proposed approach but most of them are still lacking a high level control protocol even though that this protocol is available and standardised in ISO 15118.

The situation is different for a market model. PlanGridEV has described in detail how it needs to be designed and has analysed all the necessary communication and interaction between the different market players.
To implement the market model two additional steps are needed.
1. All market players need to include the same implementation of control in their product.
2. The remuneration scheme that empowers smart charging has to be implemented.
To achieve the proposed results the stakeholders should implement the following steps:

EV Manufactures
Full implementation of an advanced standard (e.g. ISO 15118 and IEC 61851-1 to support controlled charging in all new vehicles, which allows multiple charging activities per day and modulated charging.
Enable charging at rates up to 22kW AC that can be controlled via appropriate protocols (e.g. ISO 15118 and IEC 61851-1) to provide access to the full potential of flexibility of EVs.
Implement three-phase AC chargers for all EVs that draw more than 3.6 kW to avoid unbalance in distribution networks.
Implement smart charging mechanism for home charging that can benefit from load demand management for example to increase the usage of local PV generation.
Implement smart charge control mechanisms for DC charging (if DC charging is implemented in the EV) since there are significant grid cost–effect benefits between completely uncontrolled charging patterns and controlled ones.
Increase the battery capacity. This reduces the need to recharge the EV during peak time (passive benefit) and increases the capacity of flexibility (active benefit).

Charging Infrastructure Operators and Manufactures
Ensure that all private and public charging infrastructure and charging equipment is capable of controlling EVs via ISO 15118 and IEC 61851-1.
Integrate interfaces to the DSOs to guarantee that grid friendly operation is possible.
Integrate interfaces to home and company energy management systems for increasing the usage of renewables and peak shaving to lower peak power prices (e.g. on company premises).
Integrate certified and automated metering to be prepared for business models that give benefits to the costumers if they participate in certain control schemes (e.g. Operating reserve).

Support grid-friendly infrastructure by:
Establishing a framework for reduced grid fees for charge poles / charge pole operators that have fully implemented control schemes in accordance with ISO 15118 and IEC 61851-1 and a working and qualified interface for interactions with the DSO. Reduced grid fees could be:
• Reduced prices for energy consumption.
• Reduced prices for peak power.
• Reduced grid connection fees.
Introduce a prequalification process for suitable equipment and operational principles.
Integrate interfaces between grid control systems and the charging infrastructure (e.g. through the operator of the charging infrastructure) to guarantee that grid-friendly operation is possible.
Integrate interfaces to home and company energy management systems for an increased use of renewables and power demand optimisation.
Avoid supporting uncontrolled charging by:
Calculating the adequate grid costs for the connection of charging infrastructure which is not qualified for controlled charging and therefore has to be rated as a customer with a connection that guarantees the peak power of the charging infrastructure any time of the day.
Strictly claim for adherence of the existing grid connection specifications (e.g. limits for non-symmetric loads).

Ensure that regulation demands the necessary implementations from all stakeholders as explained above to pave the way of a mass-rollout of EVs.
Update the regulatory framework to ensure that:
• The DSO can benefit also from investing in smart grid technologies instead of traditional grid extension.
• The customer can benefit from offering his flexibility by allowing to charge his EV in a grid friendly way.
Since the avoided grid reinforcements play a major role in the business case for a mass-rollout of EVs, it’s necessary to empower the DSOs to have an active role in the management of renewables and loads (charging EVs) by providing grid friendly demand management services to the market.
Allow the DSOs to calculate the above proposed change in the grid fees to promote grid-friendly charging infrastructure.

Claim for realization of the Directive 94/2014 (European Alternative Fuels Infrastructure) by implementing controlled charging equipment and mechanisms by all stakeholders as explained above to pave the way of a mass-rollout of EVs.
Support the controlled charging mechanisms and the proposed modification of the regulatory framework.
Only provide public funding or incentives for:
• EVs that fully implement ISO 15118 and IEC 61851-1.
• Charging equipment that implement ISO 15118 and IEC 61851-1 and has an interface with the DSO.
• Charging equipment that is compliant with the necessary power demand to enable the usage of flexibility and fulfils the grid connection specifications of the DSOs.
• Charging infrastructure that is connected to grids (LV/MV) with sufficient reserve for the anticipated mass-rollout.
• Charging infrastructure if the necessary certified metering is implemented at the interface that the DSO is responsible for.
• Introduction of power tariffs, to bring incentives to customers to perform controlled charging and energy management at home locations.
• In the case of power tariffs at end customers, temporary reduced costs for having an incentive to invest in EVs.
Support the proposed framework and the mechanisms that are already in charge and avoid increasing complexity by adding alternatives for available market roles (e.g. support qualified metering systems in the charging infrastructure and not moveable metering systems).

List of Websites:
For more information on the project results please consult the website or contact the project coordinator Dr. Armin Gaul (