Riders in the swarm: the new generators of household integration

Riders in the swarm: the new generators of household integration

Riders in the swarm: the new generators of household integration Energy Storage Journal
Willett Kempton, University of Delaware

Willett Kempton, University of Delaware

Solar-connected batteries enable self-consumption for individual households. But that’s just the tip of the iceberg. What happens when these individual users are connected by software, join forces and then acting together as a virtual swarm become a valuable grid resource? Sara Verbruggen reports

Before Elon Musk whipped back the curtain to reveal the PowerWall, German company Lichtblick was best known for having had some success at installing microgeneration boilers, based on a partnership with Volkswagen.

But it is the company’s clever software that is the reason for the rising market interest in partnering with it.

What many in the German solar industry describe as a fierce determination among the country’s citizens to have as much autonomy where energy is concerned — without actually going off-grid — this may be the latest chapter in the country’s Energiewende (energy transition).

And it is one where batteries need to be included.

Despite the tapering off of subsidies, Germany’s solar electricity self-consumption market has grown. The number of lithium battery storage units sold in 2016 could potentially double the amount sold since 2012.

But the ability for consumers to use more electricity generated from their own solar panels, fails to exploit the technology’s full potential.

If there is such a thing as a holy grail of the industry then it could be in the ability to take PV batteries installed within thousands of basements and garages, connect them all up, into one virtual power plant, to create a powerful grid resource.

The aggregated batteries maintain the balance in the electricity grid while allowing individual asset owners to be more proactive in how they use energy, including trading it. That’s something that Lichtblick — which translates into English as “ray of hope” — has been doing since 2010 with Volkswagen-made mini-combined heat and power plants installed in Hamburg.

Swarm leader

The software platform — Schwarmdirigent (translated roughly as Swarm Leader) — the company has developed to harness them, interacts with the grid to anticipate demand on the network, allowing the utility to generate power when the price for gas is low, compared with electricity.

Lichtblick’s software, which monitors energy usage patterns of individual combined heat and power owners in its network, knows the nearest boiler to switch on to sell power to its neighbour, earning Lichtblick a profit in the process.

Virtual power plant technology and software, which is necessary for transactive energy undertakings, could be a $5.3 billion market by 2023 according to Navigant Research.

And it is drawing global players, such as Toshiba, which in 2013 bought Cybergrid, an Austrian developer of energy management software designed to match electricity consumption with a variety of distributed generation sources.

Siemens and German utility RWE have been working together since 2012 to rollout a virtual power plant, following a pilot project that went live in 2008.

There are efforts also underway to apply such platforms to electric car charging, enabling EV batteries to act as sinks or reserves of power to stabilize the grid, and earning owners some revenues while their cars are parked up.

Following 2012 changes to the EEG (Renewable Energy Sources Act), in Germany, virtual power plants are emerging as an important tool to enable direct marketing of energy from solar, wind, biomass and other renewables.

But they can also perform important grid support functions, such as the provision of controlling power in the minute reserve range, through combining electric power from a large number of generating plants and making this capacity available to the grid operator.

Prosumer power

However, while many of these are focused on networking up large utility-scale renewable energy assets Lichtblick’s attention is on bringing on-board small-scale prosumers, working with providers of residential energy storage systems, including Sonnenbatterie, Varta and now, Tesla.

Lichtblick began exploring the compatibility of battery storage technology with its VPP platform, Schwarmdirigent recently.

The company was set up in 1998, following deregulation of Germany’s energy market, as the first green energy utility in Europe.

It soon made waves, offering private customers in Germany environmentally friendly gas, containing biogas, and by campaigning for more competition in the energy market and winning a court case in favour of greater transparency in fees for the national grid.

In 2009, Lichtblick struck a partnership with Volkswagen, giving it the rights to sell the carmaker’s CHP microgeneration boilers. By 2014 the company had installed over 1,000 of the plants, all controlled by its Schwarmdirigent software.

But last year, Volkswagen cancelled the agreement.

According to speculation in the German press the carmaker most likely broke off the deal due to Lichtblick’s failure to shift large enough volumes, as the original agreement had pencilled in 100,000 units.

Lichtblick’s official line is that it would have liked the agreement with Volkswagen to continue. Nevertheless since late 2014, Lichtblick has been showing how PV storage systems and even electric vehicle charging, are compatible with its platform.

Solar-storage synergies

By working with Lichtblick energy storage, providers can sell systems with enhanced functionality. “We see the future in providing several layers of monetization or several layers of benefits that we want to and will offer to our customers,” says Boris von Bormann, chief executive of Sonnenbatterie’s North American division.

“This is the key or base feature such as self-consumption or backup power. However, then the goal is to layer on-top different applications that the customer can benefit from, such as grid-services, energy trading, balance energy, intra-trading between Sonnenbatterie customers, making our system future-proofed.”

To do this the company’s battery systems have several key software-driven functions, including compatibility with Lichtblick’s Schwarmdirigent software. All of Sonnenbatterie’s 8000 installed units can be retroactively connected up with Lichtblick’s swarm platform.

This autumn, Lichtblick will start selling its partners’ storage systems (though not installing them) and has already taken several hundred pre-orders of Tesla’s PowerWalls.

According to Lichtblick in May the two companies will initially start their collaboration in Germany and plan to expand their relationship into new markets including other parts of Europe, the US as well as Australia and New Zealand.

The company says it is too early to go into details about this intensifying collaboration with Tesla, but Musk’s magic touch is opening doors. So far Lichtblick has had meetings in New York City. “There are a few deregulated regional power markets in the US, that are interesting for us, such as California and Texas as well as some of the east coast,” says Anke Blacha, a Lichtblick official.

Baby, you can charge my car

In Germany the company has had a couple of important pilots underway to demonstrate the versatility of its platform. In partnership with Volkswagen, Lichtblick has just finished a year-long field test of 20 electric cars in Berlin.

The R&D project shows it is possible to integrate the cars’ batteries into the grid, aggregating them together.

A key part of the project is to show that even though the priority of each battery is to have enough electricity for the car to be driven, it can also be called upon to inject electricity into the grid.

Forty test drivers put their cars through different use cases and the batteries have been monitored for performance. The results will be made available by the end of 2015.

The project also looked at how participants can be incentivized to take part.

Projects demonstrating how EV charging can be used as a grid buffering tool have been occurring worldwide. But in most of these no electricity is discharged from the cars’ batteries to the grid.

Only one other project, at the University of Delaware, has come close to showing how EVs in future might participate directly in trading electricity in their batteries with the grid, as an aggregated resource.

“Our project is different because we are charging and discharging. The cars being used are being driven by real users, commercial and individual; we qualify for and are actually participating in a real market and are being paid for providing service, subject to all of the restrictions of that market,” says professor Willett Kempton, research director, at the University of Delaware’s Center for Carbon-free Power Integration.

The project began running experimentally in 2007, leading to a joint venture in 2011 between the university and US power company NRG, called EV2G, which began generating revenues from the PJM Interconnection in early 2013.

Monthly, each of the 20 cars in the initiative are paid in the region of $150 for supplying short bursts of power needed for frequency regulation services. The individual car owner might get somewhere between a half to two thirds of this amount. The driver can schedule in advance and input a minimum level of charge that they want left in the battery. EV2G collects the payments from the grid operator and pays the owners based on the availability of their vehicles.

Projects like Lichtblick’s and the University of Delaware’s also suggest how it might be possible in future for EV owners to reduce the cost of their investment in their car, by earning revenues from providing grid services when it is parked up.

Two way chargers

A unique aspect of the EV2G project is the two way chargers allow PJM Interconnection to draw off power and also give it back to the vehicle’s battery, to help balance the grid.

In other projects, for example, EV batteries, aggregated, are modulated in terms of how much they charge up depending on the power needs of the grid. Typically, the EV’s load can be reduced following a demand response request or pricing signal. The fleet, together, supports grid balancing while never discharging energy from the vehicle to the grid. To do this, the project, which is really a microgrid, is using chargers, integrated with energy storage and also connected up to solar PV systems.

In addition to Volkswagen, Lichtblick’s partners on its EV project included SMA, which provided a smart charging station that ensures that electricity can flow back and forth between the grid and the battery in the garage.

Scientists at the Fraunhofer Institute for Wind Energy and Energy System Technology have been examining the effects of the interaction between the swarm battery and the electrical grid during the trial. The 40 drivers in the project used a special smartphone app developed by Lichtblick to schedule when they needed the car and how much battery capacity was required.

Some participants used the car as their main vehicle while others used it as their second car. The different use cases will provide important data on how batteries perform under various amounts of use.

Both Lichtblick’s project and the University of Delaware’s work are generating information on how EV batteries withstand over their deployment as a grid resource, about which there is little data, though it is dependent on how the batteries are managed and the interplay with the chemistry.

This June the EV2G initiative secured a share of a $6.5 million Department of Energy (DoE) grant to take part in NREL’s Integrated Network Testbed for Energy Grid Research and Technology Experimentation (INTEGRATE) project.

The initiative’s aim is to enable clean energy technologies to increase the hosting capacity of the grid by providing grid services in a holistic way, via a platform that is open source and interoperable.

In this way the work of Kempton and his colleagues, which has already demonstrated on a small-scale the potential for electric cars to act as an aggregated grid battery, is going to be part of a much broader initiative that is demonstrating a more expansive VPP concept.

Other technologies in the project include solar inverters, thermostats, pool pumps, community battery storage as well as bi-directional electric car chargers.


The platform will allow renewable energy systems and other clean energy technologies to be connected to a smart power grid in a plug-and-play way, just like computers allow users to plug in new devices and connect automatically to the device.

Although this sounds simple, it will require the integration and coordination of a broad mix of technologies, including different types of hardware, advanced software, monitoring, control and communication technologies. The open platform will need to enable the grid to support large-scale complex operations, interacting with distribution systems at electric utilities.

Mastering Big Data is essential to such projects becoming more mainstream. No wonder big blue chips are circling and Silicon Valley is pumping money into start-ups that are focused on wrangling distributed generation into a grid-friendly resource. In Lichtblick’s favour is the company’s ability to show how a variety of different types of distribution generation and storage technologies can interplay within its VPP platform, because in reality consumers need electricity and they need heat.

As a utility, Lichtblick is unique in that is has made considerable investment in its own software. “Many utilities made the decision to outsource the IT aspects of their businesses. From the outset Lichtblick decided it had to keep this in-house,” says Blacha.

It’s a move that may give the company an edge as the swarm gathers.