Source Data
Ellserve Source Data
Ellserve uses the following source data:
- Invoices
- Meteorology
- Emissions factors
Invoices
Invoices, obtained directly from suppliers, provide nearly all the underlying data for Ellserve's reporting and charting functions. Line by line information on every invoice processed by Ellserve (including retired invoices) is available on-screen and in downloadable form through the Invoice browser.
Ellserve extracts the following information (if present in source data) from supplier invoices:
- Supplier
- Account number
- Invoice number
- Invoice date
- Invoice period (start date and end date)
- Total commodity supply charges
- Total charge (commodity supply charges plus any balances bought forward or additional non-supply charges)
- Billed address
- GST
- Prompt payment discount
- Connection point details (e.g. ICP)
- Physical address
- Connection point ID
- Meter details
- Meter number
- Meter read type (e.g. actual/estimate/customer)
- Meter read date
- Metered usage (preferably using previous and latest reads)
- Meter reading multiplier
- Tariff lines:
- Tariff name (supply, carriage, levy, penalty, tax and rebate tariffs)
- Tariff quantity (e.g. kWh)
- Tariff rate
- Tariff charge
Meteorology
Climate data, sourced from the NIWA climate database, collected as monthly values by selected metering station can be used for reporting and charting. Where consistent historical records are available the following data climate data types are collected by station:
- Degree days heating
- Degree days cooling
- Rainfall
- Sunshine hours
- Air temperature
Emissions factors
Emissions factors are used by Ellserve to calculate the tCO2e emissions associated with various energy sources. For direct burn energy sources such as natural gas or diesel the fixed conversion factors as provided by the New Zealand Energy Information Handbook. The emissions associated with a unit of electricity consumption is proportional to the amount of thermal energy sources (as opposed to renewable sources) used in generation. Energy Link uses its database of half hourly generation by fuel type across all of New Zealand, to calculate single monthly NZ emissions factors for electricity. The methodology for creating these factors is similar to that used by the Ministry for the Environment. However, MfE's factors are calculated annually while Ellserve's are calculated monthly giving a more accurate view of actual emissions.
Note: Energy Link emissions factors are not used to calculate monthly emissions values, they are not independently available through the website.