Unlocking flexibility in smart devices

The ‘Coordinating power control’ project in Sweden is developing solutions to deliver flexibility to the distribution grid as distributed energy resources grow.
Published: Tue 20 Aug 2019

The challenge facing distribution system operators (DSOs) as smart home devices proliferate is the absence of visibility on them. There are myriad different technologies being installed by different vendors, including electric vehicle (EV) and home storage charging, heating, hot water, flexible lighting, etc.

To address this issue, the Swedish Energy Agency is supporting what it calls a “bottom up approach” project with Upplands Energi and smart device providers in the Uppland County on the country’s eastern coast. The scope is to integrate the various smart systems addressing technical, regulatory and psychological challenges to unlock their flexibility in order to optimise the distribution grid as renewable generation grows.

“In the deregulated energy market in Sweden, the concern is that as these smart systems grow they could bring down the entire bidding process in the market, while simultaneously inducing severe power peaks in the local distribution grid if their use is based only on cheap hourly energy prices,” explains Joachim Lindborg, the project technical lead at Sustainable Innovation Sweden.

 

Smart home technologies

The ‘Coordinating power control’ project, which launched in 2017 and runs through to the end of this year, is integrating 60 sites with rooftop PV providing 200kW of production, up to 500 connected water-based heating systems providing more than 1MW of flexibility, 36kW EV charging and 80kWh of home batteries providing 60kW of instant power flexibility in eight villas.

These are being connected using the openADR protocol through the respective vendors to a platform developed by Ngenic to provide forward optimisation of power usage based on forecasts and local congestions. The option is available for all resources either to participate or to opt out of the optimisation and all participants share in the value that results.

Lindborg says that the project so far has shown “substantial results”. For example, the stored energy in water-based heating in all Swedish homes could amount to as much as 6GW of flexible power, which could be used both as base control in the TSO grid as well as for peak load management in the local DSO grid.

By combining this with energy hubs, batteries and smart EV chargers, this flexibility can be used for smoothing peaks more cost effectively than traditional grid reinforcement, he says.

As an example, on 28 February 2018 the Swedish energy system was under strain with an early morning peak load of 26,700GW and locally in the DSO grid about 61MW. With the project active, 1.8MWh and more than 1MW of peak power could be removed locally. The monetary gain for the DSO was €48,500, which nevertheless received a penalty of €13,000 on the remaining power peak at 60.5MW.

Lindborg notes that the morning peak in the local grid occurs one hour before that of the system as a whole. Thus, in large scale deployments, it is recommended to differentiate on value as there will be differences in who has the most to gain from power reserves either locally or whole system. The question also arises if double benefits should be awarded for helping several systems?

He adds that scaling up the technology to provide 3-6GW of flexible power in the grid could make a “large difference” to the level of renewables that could be integrated.

Consumer satisfaction

Lindborg says that a major barrier to getting smart devices into consumers’ homes is the thought of being controlled and sacrificing comfort. However, the project has demonstrated that the level of comfort can be improved with smart usage and energy efficiency and raises consumer satisfaction as being involved in a project to support the energy transition.

On the other hand, some other barriers have been highlighted. One is the lack of clarity, especially around fire safety, in the rules for batteries in domestic housing. Another is lack of interest at government level in developing systems to support the grid and linked to that regulation that does not promote R&D by utilities.

Another concern is uncertainty around what is permitted in the way of tariff models under the current regulation, which leads to a “maybe later” mentality among DSOs. Within the current project customers achieve savings through a reduction in energy costs but with the prospect of more dynamic grid tariffs these could be extended to customers in the future, Lindborg points out.

Looking ahead, Lindborg says that Upplands Energi is looking towards the commercialisation of the solutions developed for the benefit of other customers and for example the heat pump control is already in the commercial phase.

“Customers benefit doubly,” he notes, with Upplands Energi a customer owned company for 100 years. “In addition to their own energy savings, savings for the grid owner result in lower grid tariffs.”

 

Red: actual load with active control, blue: the power curve without control based on a system model that matches the time before and after the control.