How to Leverage Green Button Initiative Data for Energy Consumption Apps

For economic, political and environmental reasons, energy use is an important consideration for U.S. citizens and policymakers alike. Two major drivers of that use — representing about 40% of total consumption last year — are the residential and commercial sectors, which require energy for a spectrum of daily needs, including heating, air conditioning, lighting and electronics.

At the same time, the greater availability of energy-related data provides a unique opportunity for developers to enter the energy space, which has historically been the purview of utilities alone. In this article, we look at the Green Button initiative, an industry-led effort to provide utility customers with easy and secure access to their energy usage information. We also consider how developers can leverage these data to help customers pursue energy efficiency and other energy goals.

The Green Button Initiative

The Green Button initiative was launched at the beginning of 2012 and represents industry’s response to a White House call to action to provide consumer energy data in both people- and computer-friendly formats. The initiative follows on the creation of a similar system for healthcare information, called Blue Button.
A growing number of electric utilities have committed to providing energy usage data to their customers through the Green Button initiative. As of this writing, the program encompassed more than 150 utilities and service providers and more than 60 million households. As we will discuss later in this article, the initiative is also benefitting from a growing number of third-party companies creating products, services and apps that utilize the exposure of these energy data.

Accessing Green Button Data

To begin, let’s consider some of the technical components of the Green Button system and, specifically, the two available options for transferring energy data to applications. For developers, the choice of which option to use will largely depend on the target market and how the utilities in that geographical area have chosen to implement the Green Button program.
The first option is Green Button Download My Data, a mechanism that allows the customer to manually download an energy data file from the utility, which can then either be used by customers themselves or, more likely, provided to a third-party application for analysis. The second option is Green Button Connect My Data, which allows customers to authorize third-party companies to receive their usage information directly from the utility, streamlining the process for both the customer and the application. Among utilities implementing Green Button, some offer only the first option (Download My Data), and some offer both.
At the technical core of these data-sharing processes is the Energy Services Provider Interface, a standard developed by the North American Energy Standards Board with support from the National Institute of Standards and Technology and the Smart Grid Interoperability Panel. According to the Green Button website, the ESPI standard ensures that "energy information can easily be exchanged without requiring developers to invest time and money to support proprietary metered data conversion technologies."
Specifically, the ESPI XML schema provides a consistent data structure for the transfer of information between utilities (termed "data custodians"), their customers ("retail customers") and authorized applications ("third parties"). The diagram below illustrates the relationships among these three actors and how the Download My Data and Connect My Data mechanisms fit within the Framework.

Source: Green Button Developer’s Guide,

As the diagram shows, Green Button Download My Data involves a transaction between the utility and its customers only. For a third party to make use of the data, the user would manually provide the downloaded file to an application, likely by using a Web interface.
In contrast, Green Button Connect My Data requires the participation of all three actors. The customer must tell the utility about the third party and grant the third party access to the information; the customer must likewise tell the third party about the utility and provide the credentials needed to connect. Once this one-time authorization is complete, the third party is able to receive data from the utility without further customer action.
Although a number of utilities offer, or are planning to offer, Green Button Connect My Data, two examples are the California utilities Pacific Gas & Electric Co. (PG&E) and San Diego Gas & Electric Co. (SDG&E). The first phase of PG&E's product, which includes access to electricity usage data, was rolled out earlier this year, and a second phase is planned for the fourth quarter. SDG&E announced the rollout of its Connect My Data Platform near the end of 2012. Both companies are soliciting registrations/applications from developers and third parties looking to create products using their customers' data.
Aside from working directly with a utility, developers can also leverage the Green Button initiative’s API Sandbox to create and test their applications. As part of Green Button’s Developer Sandbox, the API Sandbox provides a testing ground for a number of RESTful methods relating to server status, applications, authorizations and, of course, energy data itself. Finally, additional information relevant to developers can be found on the Green Button website, including videos, reference documents and sample data files. A developer's guide is also available.