BillSave interval CSV
Available in every enabled market with an email-created BillSave account or IAMMETER sign-in. Upload real 5, 15 or 30-minute kWh intervals with absolute RFC 3339 timestamps.
PRIVATE ENERGY DATA
Upload interval CSV data to calculate electricity bills
Create a private Dataset from BillSave interval CSV in any enabled market, calculate supported electricity offers and reuse the same actual usage data in Run Bill, Compare Offers and Find Best. Australia also accepts AEMO MDFF NEM12 v2.7.
ACCOUNT
Choose how to sign in
Sign in with IAMMETER or create a BillSave account with your email. Either option identifies your private BillSave workspace so Datasets, parameters, Runs and reports remain available across browsers. IAMMETER users can authorise a Cloud Site or upload a file; email-registered users can upload BillSave interval CSV data without an IAMMETER account, device or Cloud Site.
DATA SOURCES
Choose the source that matches your data
IAMMETER Cloud
Optional for IAMMETER users. Continue with IAMMETER, load an authorised Site and confirm its Grid and Controlled Load channels so no CSV upload is needed.
Australian NEM12
Australia also accepts an uncompressed UTF-8 AEMO MDFF NEM12 v2.7 file. Preview discovers kWh streams and requires you to assign each stream explicitly.
SAMPLE DATA
Try four fictional monthly load profiles
Each Great Britain sample covers the same dates with 1,488 half-hour intervals and approximately 450 kWh import. Use more than one to see how identical Offers respond to different load timing and export. The names describe fixture construction and are not labels BillSave assigns to real users.
Evening-heavy
Most import falls in the 16:00–22:00 feature band.
Download CSVOvernight-flexible
Most import falls in the 00:00–06:00 feature band.
Download CSVDaytime-home
Most import falls in the 10:00–16:00 feature band.
Download CSVSolar-export
Includes substantial daytime grid export as well as household import.
Download CSVUse the samples in the Great Britain app
Open Great Britain Run Bill, choose Uploaded data, select a downloaded file and run Preview. After Preview succeeds, enter a Dataset name and save it. The timestamps already include the correct British UTC offsets, so there is no separate timezone field.
UPLOAD WORKFLOW
Preview before BillSave saves anything
Preview validates the file, detects interval resolution, reports coverage and quality, and discovers NEM12 streams. Save Dataset is available only after the required confirmations are complete.
Sign in or create an account and open Run Bill
Create a BillSave account with your email, or continue with IAMMETER. Select a country, open Run Bill, choose an Offer, then choose Uploaded data under Energy data source.
Choose one billing month
One upload may contain no more than 32 consecutive days, 10,000 records or 5 MiB. The allowance covers a 31-day billing month and daylight-saving boundaries.
Select CSV or Australian NEM12
CSV works in every enabled market. NEM12 v2.7 is available only in Australia. The selected filename and size appear before Preview.
Preview coverage and quality
Check format, absolute timestamp offsets, interval resolution, first and last interval, energy totals, gaps, overlaps and non-actual quality. Missing energy is not changed to zero.
Confirm every NEM12 stream
Assign each discovered kWh stream to Grid import, Grid export, Controlled Load import or Ignore. Do not guess direction from a NMI suffix.
Name and save the Dataset
The name and save action appear after Preview succeeds. BillSave stores an immutable private revision; changing a stream mapping creates another revision rather than rewriting historical Runs.
Calculate, compare or find
Select a billing period contained within the saved Dataset and reuse the same immutable revision in Run Bill, Compare Offers or Find Best.
Minimal BillSave interval CSV
start_at,end_at,import_kwh,export_kwh
2026-08-01T00:00:00+10:00,2026-08-01T00:30:00+10:00,0.420,0.080
2026-08-01T00:30:00+10:00,2026-08-01T01:00:00+10:00,0.390,0.060CSV rules
- Every start_at and end_at timestamp must carry Z or an explicit UTC offset. Offset-free local timestamps are rejected.
- The timestamp text is authoritative; BillSave does not reinterpret it through a separately entered timezone.
- Every row must use the same real 5, 15 or 30-minute duration.
- kWh values must be finite and non-negative. Use zero only when energy is measured and genuinely zero.
- Optional energy columns include controlled_load_import_kwh.
- Do not fill missing intervals with invented values.
NEM12 rules
BillSave accepts AEMO MDFF NEM12 v2.7 only in the Australian market. The file must be uncompressed UTF-8 text with valid record ordering. Preview masks customer identifiers and lists discovered kWh streams.
- Grid import is electricity drawn from the network.
- Grid export is electricity sent to the network.
- Controlled Load import is only for a separately billed controlled-load circuit.
- Ignore excludes a stream from the bill.
- Use register information from the data provider or bill; BillSave does not infer direction from identifiers alone.
Resolution, completeness and quality
Real 5 or 15-minute source series are preserved and may be summed into a normal 30-minute billing series. A 30-minute source is never split into invented finer data. Estimated or substituted source intervals remain disclosed, and Offer requirements can block or downgrade a calculation when coverage or resolution is insufficient.
TROUBLESHOOTING
Why a file may not pass Preview
Timestamp has no offset
Every CSV timestamp must end in Z or an explicit offset such as +01:00. Include the correct offset on both sides of a daylight-saving change.
Mixed interval lengths
A single CSV must not mix 5, 15 and 30-minute rows. Export or normalize one consistent source series.
Gap or overlap
Intervals must be chronological and non-overlapping. Preview reports missing coverage instead of inventing energy.
More than one billing month
Split files that exceed 32 consecutive days, 10,000 records or 5 MiB, then upload the required billing month.
NEM12 mapping required
Every discovered kWh stream needs an explicit role or Ignore selection before the Dataset can be saved.
PRIVACY
Uploaded files remain private account data
Uploaded files are not placed in public URLs, analytics events or search pages. Avoid sharing complete NMI, MPAN, meter serial or account identifiers in public support posts.