Solar-use planning series · 6-minute read · Updated 5 October 2026

Your solar app and electricity bill measure different things. The app may show total generation; the bill records grid electricity and the applicable charges and credits. Neither number alone tells you how much solar electricity the property used.

This checklist helps Malaysian homeowners and business owners understand operating records. If you are still choosing an installer, use the same seven checks to ask what you will be able to verify after installation. Features vary by inverter, meters and monitoring package; confirm which values are measured and which are calculated.

1. Check the dates and missing data

Start with the beginning and end of the reporting period. A calendar-month app total will not necessarily match a utility bill covering different dates.

Look for gaps, an offline status or an incorrect time setting. Missing app data does not by itself prove the panels stopped producing. Record the gap and ask the service provider whether it is a communications issue, an equipment issue or both.

2. Record generated energy in kWh

Power in kilowatts (kW) describes the rate at a moment. Energy in kilowatt-hours (kWh) accumulates over time. Use kWh for a daily or monthly generation record, not a screenshot of the highest midday kW reading.

Compare output with the estimate for that season and site. Weather, shading, temperature and equipment availability can affect performance. The US Department of Energy’s monitoring guidance describes comparison with system models and environmental conditions. A single cloudy day is not a reliable performance verdict.

3. Record electricity imported from the grid

Grid imports are electricity bought from the utility. After solar installation, imports can be lower than total property consumption because some demand is served by the panels.

A generation-only inverter app cannot necessarily show whole-property imports or consumption. Additional measurement may be needed. Confirm the monitoring scope at handover instead of assuming every dashboard has the same sensors.

4. Record exports separately

Export is electricity flowing from the property into the grid. Use records that cover the same dates as your generation and import totals, and ask the installer to explain discrepancies between sources.

For a TNB Solar ATAP account, export credit is subject to the approved programme and billing rules. The official guideline says unused offset does not roll into later billing periods and cannot offset the Automatic Fuel Adjustment (AFA). Do not multiply every generated kWh by the full bill rate and label the result “savings”.

5. Calculate direct solar use only where the data supports it

For a simple system without batteries or other generation, using aligned AC-side records, direct solar use can be approximated as generation minus export. Property consumption is then approximately grid imports plus direct solar use. Metering boundaries, accuracy and losses can cause differences.

Illustrative energy balance: 900 kWh generated minus 250 kWh exported gives approximately 650 kWh used directly. Add 450 kWh imported and estimated property consumption is 1,100 kWh. Direct use is about 72% of generation, while solar supplies about 59% of consumption. These percentages answer different questions and neither is a bill-saving percentage.

If batteries or other generators are present, ask for an energy balance that includes their separate flows, losses and change in stored energy. The simple subtraction above cannot reliably distinguish electricity consumed now from electricity stored for later.

6. Check the bill components, not just the total

Keep the issued bill alongside the energy record. Note the tariff category, relevant credit entries, billing days and any unusual charges. TNB’s tariff information explains the current structure and monthly fuel-cost adjustment mechanism.

A lower bill may partly reflect fewer operating days or changed behaviour. A higher bill may coexist with normal solar generation if consumption or charges increased. Comparing two totals without those details does not isolate the solar contribution.

7. Log alerts and the action taken

Save the date, displayed message, affected period and relevant screenshots when an issue appears. Add any known shutdown, internet interruption or new shading. Ask the service provider what response is appropriate; do not open electrical enclosures or alter protection settings.

The Australian Government’s monitoring guide explains why access to historical generation and consumption records is useful. Its technical guidance is relevant here; its electricity-market arrangements are not Malaysian rules.

Agree how performance and support will be checked

Keep one row per period: dates, generation, imports, exports, estimated direct use where valid, bill total and notes. Before signing, ask who receives alerts, who you contact about faults, what maintenance is recommended, and which call-outs or replacement costs are excluded. Request the actual equipment and workmanship warranty terms in writing.

Evolts lists monitoring, cleaning and health checks within its solar maintenance and project services. Confirm the scope included in your own proposal; a listed service is not a promise that every package includes it.

What happens when you contact Evolts

1. Say whether you are planning a new system or already run one. Send a recent TNB bill and a roof photo; if you already have solar, add records that cover matching dates.
2. An engineer replies within one working day. For a new system, that includes an indicative system size, cost band and payback estimate. For an existing system, ask what an assessment of your equipment would involve and what it would cost.
3. Agree the monitoring scope in writing before you sign: the sensors, data access, alerts, response arrangements and any fees.

Questions owners ask before enquiring

Need to clarify the usage assumptions first? Return to the home daytime-usage checklist or the factory weekend and shutdown checks.