VoltCalc

The Problem

Bangladeshi consumers struggle to predict stepped-tier electricity bills, decode complex statutory adjustments (demand charge, 0.5% rebate, 5% VAT), reverse-engineer prepaid meter recharges, or audit household appliance power consumption.

What It Does

• ✓Official BERC LT-A domestic tariff matrix with Life Line (0–50 units) and progressive tiers up to >600 units
• ✓Statutory charge calculations: ৳42.00/kW demand charge, 0.5% rebate, and 5.0% post-rebate VAT
• ✓Reverse prepaid calculator inverting VAT, rebate, and fixed charges to compute exact kWh units from Taka recharge
• ✓Household appliance load auditor with Bangladeshi wattage defaults, compressor duty cycles, and vampire standby tracking
• ✓Sanctioned demand load estimator applying ~65% diversity factor on connected peak load
• ✓Interactive what-if simulator testing runtime adjustments and visualizing instant monthly kWh/Taka savings
• ✓100% client-side zero-latency architecture with persistent state synchronization using useSyncExternalStore and localStorage

How It Works & Architecture

Technical Challenges

• !Designing exact inverted math engine to reverse-engineer progressive stepped tariff slabs from gross recharge amounts including VAT and rebate deductions.
• !Accurately modeling non-linear appliance duty cycles (compressor/thermostat cycling) and standby vampire power.

What I Learned

• ★Client-side pure mathematical models provide instant feedback with zero server costs and total user data privacy.
• ★Decoupling calculation engines from UI components enables seamless forward, reverse, and appliance load synchronization.