Electricity Slab Tracker App That Warns Before You Lose the Protected Tariff

The problem: the bill arrives after the damage is done

Electricity bills in Pakistan have risen sharply in recent years, and for many households the bill is now one of the largest monthly expenses. Domestic tariffs use slabs, and as widely reported, a household that stays at or under 200 units a month is treated as a protected consumer with lower rates; crossing that line in a single month can remove the protection for the following six months. A hot week with the air cooler running longer can push a household over without anyone noticing until the bill arrives, by which time the expensive months are locked in.

Households can read their own meters, but turning a few readings into a forecast for the billing cycle, and knowing where the slab lines fall, is not something most people do.

What already exists and the gap

• Bill checking websites and distribution company apps let consumers view and download issued bills. They show what happened, after the cycle ends.
• Tariff calculators online estimate a bill from a number of units, if you already know the units.
• Smart meters with in-home displays solve this elsewhere, but most Pakistani homes have conventional meters.

The gap is a simple forward-looking tool: from the readings you take during the month, how many units will you end at, what will it cost, and how close are you to a line that changes everything.

Inspiration

The Effectiveness of Feedback on Energy Consumption (Sarah Darby, Environmental Change Institute, University of Oxford, 2006), a review for the UK government, examined studies of metering, billing and direct displays and found that direct, frequent feedback on consumption is consistently linked to savings. This project brings frequent feedback to households without smart meters, using their own readings.

What you build

• Households enter the reading from their meter every few days, with a photo for their own record. Reminders help them keep the habit.
• The app shows the units used so far this cycle, the forecast for the end of the cycle as a range, the estimated bill and the slab or protected limit they are heading towards.
• A warning appears when the forecast range crosses a threshold, with a simple suggestion of how many units a day they need to stay under.
• The appliance planner shows roughly what an hour of a fan, cooler, iron or air conditioner adds, so the warning is actionable.

The technically interesting part

• Forecasting from sparse readings. Readings arrive at irregular times. Fit a daily usage rate from the history, account for the days remaining and give a range that widens with uncertainty. Compare a simple linear projection with one that weights recent days more, and check both against actual bills.
• Tariff rules as data. Slabs, rates and the protected condition change through regulator decisions. Store them as versioned JSON with a source and effective date, so an update does not need a new app release. Write tests for every rule.
• Billing cycles that do not match calendar months. Meter reading dates vary, and units must be pro-rated correctly between readings.
• Clarity. A warning that is wrong or confusing will be ignored. Design and test the wording with real users.

How to evaluate it

• Forecast accuracy: for households in a pilot, compare the forecast made ten and five days before the reading date with the units on the actual bill.
• Tariff correctness: tests that compare your bill estimates with real bills for a range of unit counts.
• Pilot: ten or more households using the app for two billing cycles; record whether warnings were understood and whether any household changed behaviour.
• Usability: can a user who has never seen the app enter a reading in under 30 seconds?

Suggested plan

• Weeks 1 to 3: collect the current tariff schedule from the regulator's published documents and some real bills (with permission); write the rules as data with tests.
• Weeks 4 to 7: reading entry, cycle setup and the forecast.
• Weeks 8 to 10: warnings, appliance planner and reminders.
• Weeks 11 to 13: pilot with households.
• Weeks 14 to 15: analysis, report and demo.

Path to a product

Every household with a meter is a potential user, and the need grows with each tariff rise. The app could be free with optional sponsorship from solar or efficient appliance companies, as long as advice stays neutral. It is a good first mobile project because the logic is clear, testable and useful to people you know.

Scope warning

Always confirm the tariff rules against the current official schedule and show the date of the rules in the app; never present an estimate as an official bill. Do not try to read meters automatically from photos in this version; manual entry is enough. Keep readings on the device unless the user chooses backup.

Learn what you need on Sefism

• Mobile development roadmap: building and testing a first real app.
• Flutter Documentation: the app framework.
• Dart Language Tour: the language behind Flutter.
• Material Design 3: clear layouts for numbers and warnings.
• Data analytics cheat sheet: checking forecast accuracy honestly.

Get help with this idea

The hard parts are keeping tariff rules correct and writing warnings people act on. Tauseef can help you structure the rules as data, plan the pilot and present the forecast results well. If you are new here, create a free account first.

• Discuss this idea with a mentor
• Send a query to Tauseef
• Book a 1:1 session