Energy data management for building portfolios: Green Button and bill PDFs in one view

Ask a property management company where its energy data is and the answer is usually: in the accounts payable system, in a folder of PDFs, in a spreadsheet someone built in 2021, and in three utility portals with three passwords. Each of those holds part of the truth. None holds all of it, and none holds it in a form that can be compared across buildings or months.

Energy data management is the work of fixing that. This article describes the sources, the structure, and the rules that make a portfolio's utility data usable, and how VE-MAP implements them.

Two sources, two shapes

Bill PDFs

Every account produces a bill, and the bill is the record the money is paid on. It carries the account and meter identifiers, the service period, consumption, demand where applicable, each charge line, taxes and the amount due. Layouts differ by utility and change over time; multi-meter accounts spread one invoice over many pages; scanned bills lose their text layer. Reading bills reliably means a text-layer parser with rules for each layout, a fallback to image reading, and a reconciliation step that checks the extracted charges add up to the printed total before the bill is trusted.

Green Button

Green Button is the standardized format for utility usage data. In Ontario, the province's energy data regulation required electricity and natural gas utilities to implement Green Button Download My Data and Connect My Data and to have them certified by November 1, 2023; the Green Button Alliance certified 55 utility platforms, covering nearly all of the province's 5.4 million electricity customers and over 3.5 million natural gas customers. Connect My Data lets a customer authorize a third party to pull interval usage and billing data directly, which is how the platform receives meter data without anyone downloading files.

The structure

Whatever the source, every record ends up in the same shape: portfolio, building, commodity, account, meter, period start, period end, quantity, unit, cost, source, and a link to the original document or feed record. From that one table everything else is a query: monthly consumption per building, cost per commodity, intensities per square foot, year over year comparisons, Portfolio Manager exports.

• Buildings carry floor area, units or beds, address and property type, because every intensity divides by one of them.
• Meters carry friendly names, because Green Button account identifiers mean nothing to a superintendent.
• Periods carry both dates, because the reporting month is derived from them, not from the bill date.
• Sources are retained. The PDF, the Green Button record, the RETScreen import and the manual correction are all kept, with the correction noted, so any number in a report traces back.

The rules

One calendar

Bills straddle month ends. The platform assigns each period to a reporting month by a single rule (start day before the 15th means that month, on or after the 15th means the next month; invoices over 45 days are prorated), applied to PDFs, Green Button and RETScreen alike. The validation article explains the rule and its consequences.

One value per meter-month

When a PDF and a Green Button record cover the same period, one is chosen as the value for the month and the other is retained for comparison. The choice is consistent per commodity and is visible in the Bills Manager, so double counting cannot happen silently.

Units that add up

Electricity in kWh, gas in cubic metres, water in cubic metres, district energy in the unit the supplier bills. Energy totals and intensities are expressed in equivalent kWh so electricity and gas can be summed, and ENERGY STAR's definition of EUI (energy divided by gross floor area) is applied the same way for every building.

History that does not expire

Utility portals show a limited window. The platform merges each new Green Button pull with what it already holds, so months that age out of the utility's window remain in the portfolio's history. That matters for M&V baselines and for the multi-year view in the annual benchmark report.

Names people recognize

Green Button identifies meters by long account and service point identifiers. The platform lets a reviewer give each meter a friendly name (house meter, garage, retail unit) that is used everywhere the meter appears, including the monthly review. Bills can be filed into folders per building or per year so that an auditor or a new property manager can find a document without knowing the system. Small things, but they decide whether the data is used by the people who need it or only by the person who set it up.

What good data management makes possible

• Benchmarking: intensities per building against portfolio and peer averages, and the annual EWRB benchmark report described in Ontario EWRB reporting.
• Monthly review: the report structure depends on complete, validated months.
• M&V: a baseline is only as good as its data; see weather normalization, CUSUM and RETScreen M&V.
• Emissions: greenhouse gas totals computed from consumption with published factors, covered in GHG emissions from utility data.
• Filing: ENERGY STAR Portfolio Manager meters kept current by pushing validated months.
• Reporting: monthly rows pushed to Power BI for teams that build their own dashboards.

Signs your current setup is not working

• The same building shows different annual totals in two internal reports.
• Someone downloads Green Button files by hand each month.
• A bill that failed to parse was simply left out, and nobody noticed the month is missing.
• Floor areas differ between the Portfolio Manager account and the internal spreadsheet.
• The M&V baseline lives in one person's RETScreen file.

FAQ

Do we have to use Green Button?

No. Bill PDFs alone produce monthly consumption and cost. Green Button adds interval data and an independent check on the bills. Where the utility offers it, connect it.

What happens to bills that will not parse?

They are flagged, not dropped. A reviewer enters or corrects the values in a fix dialog, the correction is marked and noted, and the original PDF stays attached.

Can we export everything?

Yes. Reports export to PDF and Word, benchmark reports to Excel, and monthly rows to Power BI and Portfolio Manager. See the use cases page for the configurations, and the portfolio view article for the overall path.