How Lunar Energy is using AWS to create a customer-led energy system

Lunar Energy (Lunar) has a mission to power homes around the world with endless clean energy. Recognizing the urgent need to reduce carbon emissions and combat climate change, Lunar is focused on building the digital infrastructure needed to build a resilient, distributed energy system. As homes electrify by adding distributed energy resources (DERs)—such as solar panels, batteries, and electric vehicles—they reduce their emissions. By optimizing the schedule on which those connected devices use and generate electricity, virtual power plants (VPPs), made up of millions of homes, can play a role in keeping the power grid clean and stable. Being able to intelligently manage consumer demand as a balance against fluctuations in renewable generation means that the grid can remain even and uncongested as it decarbonizes, driving down cost and emissions for the system as a whole—and without the need for peaker plants that use gas.

Lunar’s Gridshare platform is a cloud-based home energy management system (HEMS) and VPP service that connects to third-party DERs and optimizes them to simultaneously deliver value for customers and the grid. Lunar is also building a residential battery system that combines best-in-class hardware, ease of installation, and a superlative customer experience with best-in-class VPP software. Homes can not only generate their own virtually endless clean energy, but they can also share it with the grid for a cheaper, cleaner system that also benefits neighbors who don’t have DERs.

Figure 1. Lunar Gridshare’s current global footprint and near-term growth

Lunar Gridshare is connected to 77,000 residential devices across Europe, Japan, and the United States, representing 290 megawatts of power and 725 megawatt-hours of energy capacity. This is enough to power 578,000 average US homes for one hour. Devices on the platform increased by 10 times from 2019 to 2021—and then again by the same amount from 2021 to 2023. In Japan, Gridshare is connected to 37,000 residential batteries installed by its partner ITOCHU, delivering daily behind-the-meter optimization that reduces customer bills. Over the past year, Gridshare has been working with four of the five largest Japanese power companies to deliver demand response solutions and help them reduce their wholesale procurement costs. In the United States, Gridshare is aggregating and dispatching third-party batteries to deliver all of Sunrun’s VPP contracts. Gridshare is also delivering the smart control behind Honda’s e:PROGRESS EV charging service.

The challenge

DERs will play a critical role in lessening society’s reliance on fossil fuels through electrification. Decarbonizing the grid by 2050 will require not only 35 million new EVs to be on the road each year through to 2030 but also the addition of 455 gigawatts of solar and 245 gigawatt-hours of battery storage in the same period.¹ Electrification at this pace poses challenges to both energy retailers and grid operators. Energy retailers may sell less electricity as customers generate and store their own. At the same time, those same retailers will have to actively manage their energy portfolios to accommodate changing consumption patterns because large amounts of energy will be required to power electric devices. At a system level, as more renewables come online and increase the complexity of both generation and consumption patterns, network congestion and balancing will throw up new challenges—but also new opportunities. For instance, where there are high but infrequent demand peaks in a neighborhood, software-based flexibility services can help avoid—or delay—the need to install a new and expensive transformer at the local substation. For end customers, this means earning money from energy rather than just paying for it.

A scalable, customer-centric solution

To address these challenges in a way that delivers value to customers while decarbonizing the grid, it is critical to be able to securely connect to, manage, and control millions of high-power devices in customer homes.

As a combined HEMS and VPP service, Gridshare can deliver value to end users by learning each customer’s energy needs and determining the optimal control plan for a home’s devices on a day-to-day basis. Gridshare forecasts each home’s consumption and production patterns and uses these insights to optimize multiple devices in the home so that they function in a way that balances the best interests of the end user and energy service provider. This detailed customer knowledge then allows Gridshare to deliver highly optimized VPP services to the grid operator or retailer based on the aggregation of all customer behavior profiles. These services can serve multiple purposes: reducing congestion on local lines; addressing overvoltage issues; balancing supply to demand at a transmission level; and providing cost savings or revenue opportunities to retailers in the wholesale market. Because Gridshare can co-optimize between the customer bill and VPP service revenue, Lunar ensures that whenever a customer asset is used for the grid’s needs, the customer is getting the best value possible. Customer-centric VPPs like this are essential in the energy transition because if electrified homes cannot provide flexibility to the energy system, the grid will struggle to accommodate increased renewable generation and peak demand. EVs, heat pumps, and batteries won’t scale at the rate needed to decarbonize the grid. To help deliver this complex functionality at scale, Gridshare uses AWS.

Figure 2. A live view of ITOCHU’s residential battery fleet in Japan, managed by Gridshare

AWS and Gridshare

Figure 3. High-level architecture of the Gridshare platform

The scalability and robustness of AWS services are at the core of Gridshare’s serverless architecture:

• AWS IoT services are used to categorize the various devices that can exist on a customer site and then get that data to the cloud via Message Queuing Telemetry Transport (MQTT), a lightweight and widely adopted messaging protocol.
• Amazon Kinesis, which cost-effectively processes and analyzes streaming data at any scale as a fully managed service, is used to stream over 230 GB of raw data from DERs each day.
• AWS Lambda—a service for running code without thinking about servers or clusters—is used to manage event-driven flows at scale across tens of thousands of devices, with functions that create daily optimization plans or deliver VPP services.
• AWS Step Functions, which provides visual workflows for distributed applications, is used to coordinate AWS Lambda workflows that manage the forecasting, optimization, and control processes across the device fleet.
• Amazon OpenSearch Service—which makes it simple to perform interactive log analytics, near-real-time application monitoring, website search, and more—is used as a hot storage layer for telemetry.
• Amazon Cognito, which provides an identity store that scales to millions of users, is used to securely manage customer credentials.
• Amazon Simple Storage Service (Amazon S3)—an object storage service offering industry-leading scalability, data availability, security, and performance—is used to securely and durably store power data from homes and devices.
• Amazon Redshift, which offers the best price performance for cloud data warehousing, is used to provide quick access to warm data at scale.
• Amazon CloudFormation—with which companies can model, provision, and manage AWS and third-party resources by treating infrastructure as code—and Amazon CloudWatch—which collects and visualizes near-real-time logs, metrics, and event data in automated dashboards—are used to help manage deployment and monitoring.
• Amazon DynamoDB, a fast, flexible NoSQL database service, is used as a multipurpose database tool across the platform.
• For cybersecurity, Lunar uses the encryption of data at rest provided by AWS for all its storage services and fine-grained identity and access management (IAM) roles for each resource to build a system with secure primitives.

Alongside this technical collaboration, AWS has supported Lunar’s near-term commercial goal of becoming an AWS Solutions Partner. Through the Grid Modernization team in its Energy Business Unit, AWS is working with partners such as Lunar to help utilities integrate more renewables into their grids with the flexibility provided by VPPs.

“To be able to deliver energy solutions that provide optimal value for customers and the grid at the same time requires the ability to connect to, manage data from, and control millions of customer devices at once. That depends on a truly robust and scalable architecture. AWS delivers that scalability and robustness for Gridshare and our customers.” —Chris Wright, Senior Vice President of Software Technology and Product at Lunar Energy

What does this mean in practical terms? Gridshare processes nearly 178 TB of residential energy data each year. When onboarding a new energy service provider, Gridshare added its fleet of 20,000 residential batteries to the platform in a month. Thanks to Gridshare’s bespoke household energy predictions, and its artificial intelligence-driven smart device control, ITOCHU customers in Japan save an extra 14 percent on their energy bill compared with relying on their battery’s default mode. With detailed forecasts of every home’s energy flows the next day, Lunar can also create accurate fleet-level capacity predictions. Because Gridshare is an HEMS as well as a VPP, Lunar can deliver aggregated VPP services in an optimal way considering each device’s power conversion efficiency—alongside cost to the end customer. Because of its robust architecture, the engine is also able to run within a few minutes of delivery across a large fleet of homes. This shortened response time facilitates more advanced trading and revenue generation. All in all, this means Lunar’s VPP engine delivered 60 percent more energy than a well-known VPP service from the same assets over the same period in a blind trial.

With more value created for customers and the grid, Gridshare lets energy businesses deliver innovative energy solutions to drive profitability and accelerate the energy transition.

Figure 4. Gridshare dispatching Sunrun’s residential batteries to deliver VPP services to Peninsula Clean Energy in the San Francisco Bay Area – Click the image to view the animated gif.

What’s next for Gridshare?

Lunar is currently working on expanding its managed assets globally, helping companies win in the new energy economy through the power of customer-sited batteries, EVs, and heat devices. Go to Lunar’s Gridshare page to learn more. Read more about AWS support for utility sustainability, its collaborations to transform, innovate, and accelerate the energy transition, or the Climate Pledge—the commitment by AWS to be net-zero across its business by 2040, 10 years ahead of the Paris Agreement target of 2050.

¹ BloombergNEF, New Energy Outlook 2021, July 2021.