RDjarbeng/rwanda-energy-calculator-js

User Interface to calculate energy units (kW/h) for Rwanda energy group based on RWF inputs and vice versa. Javascript implementation # Rwanda Energy Calculator A fast, fully static web app for calculating electricity costs based on Rwanda Energy Group (REG) tariffs. It requires no server, no build step, and no dependencies, running on pure HTML, CSS, and JavaScript. > **Original calculator logic** by Ian Akotey > **User Interface** by Richard Djarbeng (RDjarbeng) ## Related * 🐍 **Python version:** rwanda_energy_calculator (the original FastHTML/Python implementation this JS version is based on) --- ## Features ### ⚡ Calculator * **Amount → Units:** Enter how much you are paying (RWF) to see exactly how many kWh you will receive. * **Top-up mode:** Enter a previous balance to account for tier-offset pricing (units are cheaper at the start of the month). * **Units → Cost:** Enter units consumed (kWh) to get the full cost breakdown. * **Detailed billing:** View a full per-tier breakdown showing Tier 1, Tier 2, and Tier 3 usage and cost. * **VAT:** The 18% tax is calculated and shown separately. ### 🏠 Household Estimator * Select appliances from a preset list and set quantities. * Estimate your monthly and daily kWh consumption and overall bill. * View a consumption breakdown to see which appliances use the most power. * Adjust wattage and hours per day for each appliance to get accurate results. * Add custom appliances with a name, icon, wattage, and daily usage. ### 📊 Usage Tracker * Interpolate data from units purchased and current consumption to predict your next recharge date. * Easily track when your units will run out based on your current household consumption. ### ⚙️ General * **Tariff toggle:** Switch between the current October 2025 tariffs and the legacy 2020–2025 tariffs. * **Fully responsive:** Works seamlessly on both desktop and mobile devices. * **Real-time calculations:** Results update instantly as you type or adjust quantities. --- ## Tariff Structure ### October 2025 (current) | Tier | Consumption | Rate | | --- | --- | --- | | Tier 1 | 0 – 20 kWh/month | 89 R …