The shortest useful rule is to choose the data path before the dashboard. Emporia, Sense, and HomeWizard document user-facing CSV exports, but with different delivery methods, ranges, resolutions, and access conditions. Shelly documents a device-local data API instead. Those are four materially different ownership models, even though every product can display an energy chart.
This comparison is about supported data access, not measurement accuracy or which monitor identifies appliances best.
Do not sum power rows as though they were energy
Emporia’s current export guide makes a consequential distinction: its second, minute and 15-minute files contain kW, while hourly and daily files contain kWh. Keep the unit with the filename when importing a spreadsheet.
For an illustrative interval-average series of four 15-minute readings at 2, 1, 3 and 2 kW, energy is (2 + 1 + 3 + 2) × 0.25 = 2 kWh. Adding the values and labelling the result 8 kWh would be wrong. Apply this conversion only when the field represents average power over the stated interval; an instantaneous sample needs an appropriate integration method and assumptions.
Before analyzing a real export, check whether timestamps mark interval starts or ends, how missing intervals are represented, and which time zone applies. Daylight-saving changes can produce days that are not 24 hours long. Preserve the original file and make calculations in a separate copy.
The numbers above are a teaching example, not an inspected customer export. Emporia’s documentation supplies the file-unit distinction; verify the actual column definitions for the platform and export version you receive.
Current data-portability matrix
| Platform | Supported path | Resolution and range documented | Access condition | Best fit |
|---|---|---|---|---|
| Emporia Energy | Request raw data in the app; receive an emailed ZIP containing CSV files | Multiple resolution files; the retrieved guide limits its one-second file to three hours | No subscription requirement stated on the export page | Spreadsheet users who want several time scales |
| Sense | Export from the Usage screen to the device or another app | Hourly or daily rows; up to one year per export | Up to five exports per day | Home or detected-device history in a simple CSV |
| HomeWizard Energy | Export graph data to CSV | 15-minute data up to 365 days; daily data with an unlimited documented range | Energy+ | Long-range meter, tariff, import, and export records |
| Shelly Gen2 EMData | Retrieve stored intervals and values through local RPC calls | Timestamp-selected records; oversized responses are chunked | Compatible device, firmware, and technical setup | Local integrations and people prepared to handle structured data |
The table exposes the first important distinction: a downloadable CSV and a local API are not interchangeable. CSV is ready for a spreadsheet. A local RPC path can be more flexible and less cloud-dependent, but it needs code or an integration to turn responses into a durable archive.
What each platform actually gives you
Emporia: several CSV time scales in one archive
Emporia’s current export guide documents an in-app Export Raw Data to CSV path. You choose a device and date range, then receive an email with a link to a ZIP archive. The archive contains separate CSV files for different time resolutions.
That is useful when one task needs coarse history and another needs a short high-resolution window. It does not mean every resolution is retained for every date range: the retrieved documentation limits the one-second file to three hours. Treat the resolution list and its time window as one specification.
For the current product decision, see the Emporia Vue ownership and setup analysis . The export matrix answers a narrower question: whether the measurements can leave the app in a reusable file.
Sense: easy CSV, explicit one-year and daily-rate limits
Sense documents CSV export from the detailed Usage screen. An export can include the entire home with devices broken out or one selected device. The available row interval is hourly or daily, and one request can span up to one year.
Sense also states that users may export up to five times per day. That is not a problem for an occasional backup, but it matters to anyone imagining the app export as a high-frequency automation feed.
The distinction between whole-home pattern detection and circuit-level monitoring is covered separately in Emporia Vue 3 versus Sense . Do not infer detection accuracy from the CSV controls.
Sense is retiring consumer access to its web app on September 30, 2026. Its web-app notice confirms that mobile access and mobile CSV export continue, with historical data preserved. A workflow that depends on a desktop browser needs to account for that change.
HomeWizard: clear range rules, but CSV belongs to Energy+
HomeWizard’s June 2026 documentation places CSV export inside Energy+. It documents two useful range rules:
- 15-minute rows can cover no more than 365 days in one export.
- daily rows have an unlimited documented range.
Depending on the connected meter, the file can include imported and exported electricity, tariff registers, maximum consumption by phase, gas, and water. That makes HomeWizard unusually explicit about both the interval and the fields, but buyers must include Energy+ in the access decision. An export feature behind an ongoing plan is different from an unconditional device capability.
Shelly: local records, not a one-click spreadsheet promise
Shelly’s Gen2 EMData documentation
exposes saved intervals and values through EMData.GetRecords and EMData.GetData. Requests can specify timestamps, and large responses are chunked.
This is the strongest local-access route in the four-source sample, but it is also the most technical. The documentation does not turn the RPC response into a polished CSV backup for you. A compatible device, correct firmware, a local network path, and an integration or script are part of the real ownership cost.
If local processing matters more broadly, compare local and cloud-only home-energy management after deciding how much setup you are willing to maintain.
Use a two-axis test: resolution and range
“Exports data” is too weak a requirement. Ask two questions together:
- What is the smallest available interval?
- How far back can that interval be exported?
An hourly file covering a year can be better for seasonal comparison than one-second data retained for a few hours. A daily archive can preserve a long ownership history while hiding short cycling. Neither is universally better.
Use the interval that matches the job:
| Job | Useful starting interval | Why |
|---|---|---|
| Bill and seasonal comparison | Daily or hourly | Keeps files manageable and preserves broad patterns |
| Heating or cooling cycles | Hourly, sometimes finer | Shows repeated demand without requiring second-level data |
| Short appliance investigation | Minute or second-level window | Reveals a brief event, provided the high-resolution range covers it |
| Long-term backup | Daily plus documented units and timestamps | Favors continuity and readability over live detail |
There is no evidence-based reason to require every buyer to have twelve months of high-resolution data. The correct requirement depends on the task and the product’s documented range.
Check what survives outside the app
A portable record needs enough context to remain intelligible. Before buying, verify whether the exported or retrieved data carries:
- timestamps and their timezone meaning
- units such as watts, watt-hours, or kilowatt-hours
- whole-home, circuit, channel, or device identifiers
- user labels, if those labels matter to the analysis
- imported and exported energy as separate fields for solar homes
- tariff or phase fields when the meter supplies them
- a stable way to repeat the export
Do not assume an attractive chart proves any of those fields leave the system. Likewise, do not assume an API guarantees a complete historical archive. The documentation must state what is stored and how it is retrieved.
Match the access model to your tolerance for upkeep
Choose a user-facing CSV path when you want occasional spreadsheet analysis, a handoff file, or a periodic personal backup. Choose a local structured path only when you are willing to own the integration, format conversion, authentication, storage, and failure monitoring.
Subscription-gated export deserves its own decision. It may be entirely reasonable when the plan also funds useful analysis, but the ongoing requirement should be documented before purchase, not discovered when the first annual backup is due.
For privacy, export is only one layer. Account sharing, cloud retention, deletion, and local-network behavior need a separate review; use the home energy monitor data privacy checklist for that boundary.
Methodology and limits
This update reconciled four current first-party documentation sets on August 25, 2026. The reusable dataset records each platform’s access path, delivery method, documented range and resolution, available fields, subscription boundary, provenance, and uncertainty, then retains three cross-platform findings.
Sentinel did not install a monitor, request an export, inspect a delivered file, test an API, measure data accuracy, or verify historical completeness. The matrix records supported paths as documented. It does not establish uptime, export delivery speed, future pricing, future retention, cloud longevity, account portability, or measurement accuracy.
Sources
- Emporia: Exporting and Analyzing Data
- Sense: Can I Download My Sense Data?
- HomeWizard: How to export and use CSV files
- Shelly Gen2 EMData technical documentation
The useful buying question is not “does it have an app?” It is “what data can I take out, at what resolution, over what range, and under what access conditions?”