Offering Green Button Connect My Data as a utility
Green Button Connect My Data lets customers authorize secure, automated sharing of their usage data. Here is what the standard requires and how to implement it well.
Customers increasingly expect to share their own energy data with the apps and providers they choose, the same way they share banking data. Green Button is the standard that makes that possible for utility usage data, and Connect My Data is the part of it that turns a one-time customer authorization into secure, automated data sharing. For a utility, offering it well is both a customer-service commitment and a data-quality commitment.
Green Button is not new or experimental. It is based on the Energy Services Provider Interface (ESPI) data standard released by the North American Energy Standards Board (NAESB) in the fall of 2011, and today utilities in nearly all 50 U.S. states, two Canadian provinces, and the Republic of Korea offer Green Button solutions. It began as a White House initiative in 2012, when nine major utilities and suppliers committed to give more than 15 million households access to their own usage data.
Download My Data vs Connect My Data
Green Button comes in two access methods, and the difference matters when you decide what to offer.
- Download My Data (DMD): the customer manually selects and downloads their usage from the utility website in a standardized XML format, replacing the inconsistent CSV files that used to differ from one utility to the next.
- Connect My Data (CMD): an automated method that lets a third-party application securely retrieve a customer's usage data after a one-time customer authorization, with data available in 15-minute, hourly, daily, or monthly intervals.
DMD is a file the customer hands off once. CMD is an ongoing, authorized connection. CMD is the more capable option and the one that supports third-party energy services, but it also carries the heavier implementation and security requirements.
What the standard actually requires
The ESPI standard has two components: a common XML format for energy usage information, and a data exchange protocol that automatically transfers data from a utility to a third party based on customer authorization. In practice, a compliant CMD implementation rests on a few well-defined building blocks.
| Building block | Standard | Role |
|---|---|---|
| Data format | ESPI Energy Usage Information (XML) | Consistent structure for usage across utilities |
| Delivery | Atom Syndication Format | How usage resources are published and retrieved |
| Authorization | OAuth 2.0 | Customer grants and can revoke third-party access |
| Transport security | TLS 1.2 or higher | Protects data in transit |
The authorization model is the important part for customer trust. Under current NAESB ESPI practice, utilities implement the OAuth 2.0 authorization framework so the customer, not the utility and not the third party, decides who gets access and can withdraw it. The customer is in control of the connection at all times.
Why data quality decides the customer experience
A Green Button feed is only as good as the data behind it. If the interval data a utility publishes contains gaps, estimated values or anomalies, every downstream app inherits them, and the customer sees the utility as the source of the problem. That is why the meter data management and validation work that happens before publication matters as much as the API itself. Clean, validated interval data in means trustworthy Green Button data out.
The same is true in reverse for anyone receiving Green Button files. A standardized XML format solves the syntax problem, but it does not guarantee the values are complete or correct. Files still need to be parsed, checked for missing intervals and reconciled against expected usage before they can be relied on.
Implementation notes for utilities
- Decide the scope: DMD alone is a lighter lift, but CMD is what enables authorized third-party services
- Publish validated data: run interval data through validation before it reaches the Green Button feed
- Implement authorization carefully: OAuth 2.0 with clear consent, scope and revocation for the customer
- Secure the transport: TLS 1.2 or higher, and treat retail customer data as personally identifiable information
- Test against the format: confirm exports conform to ESPI so third parties can consume them without custom handling
ESPI makes the structure consistent across utilities. It does not, on its own, make the values complete or correct. Validation before publication is what earns customer trust in the feed.
How MartinAI helps on both sides of Green Button
MartinAI works with Green Button data wherever it appears in the flow. For a utility preparing to publish, it validates the interval data feeding the feed so what customers and third parties receive is complete and consistent. For anyone consuming Green Button exports, it parses the ESPI XML, checks for gaps and anomalies, and turns the files into clean records ready for analysis, billing checks or program reporting.
- Parse Green Button ESPI XML into consistent, structured records
- Detect missing intervals, gaps and anomalous values
- Reconcile usage against expected patterns and history
- Deliver analysis-ready data to billing, analytics or reporting
Frequently asked questions
What is Green Button Connect My Data?
Connect My Data (CMD) is the automated Green Button access method. After a one-time customer authorization, a third-party application can securely and repeatedly retrieve that customer's usage data from the utility, available in 15-minute, hourly, daily or monthly intervals. It differs from Download My Data, where the customer manually downloads a file.
What standard is Green Button based on?
Green Button is based on the Energy Services Provider Interface (ESPI) data standard released by the North American Energy Standards Board (NAESB) in 2011. ESPI defines a common XML format for usage information and a data exchange protocol that transfers data to a third party based on customer authorization, using OAuth 2.0 and TLS 1.2 or higher.
How does Green Button protect customer privacy?
Connect My Data uses the OAuth 2.0 authorization framework, so the customer grants a specific third party access and can revoke it. The utility does not share data without that authorization, and current practice requires TLS 1.2 or higher to protect data in transit.
Does the Green Button format guarantee clean data?
No. ESPI makes the structure consistent across utilities, which solves the format problem, but it does not guarantee the values are complete or correct. Interval data should be validated before it is published to a Green Button feed, and received files should be checked for gaps and anomalies before being relied on.
Green Button Connect My Data (CMD) for Energy Managers and Resellers
Connect My Data gives authorized third parties ongoing, automated access to a customer's utility data. Here is how CMD differs from Download My Data, how the authorization works, and what it enables for analysis and reporting at scale.
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