Sun Apex, Ambegaon

Sun Apex is a residential and commercial development by the Mittal Group at Ambegaon, in south Pune, on a sloping plot of 15,557 sq m with 53,400 sq m of construction. Four residential wings rise twenty floors above lower, middle and upper ground levels and basement parking levels that step down the slope; wings A and B hold 78 flats each, from two-bedroom homes to duplexes, and wings C and D 120 each. An affordable-housing (MHADA) building adds 33 two-bedroom flats, and twelve showrooms line the lower, middle and upper ground floors of wing A. A project of 429 homes on a hillside needs its power brought in at high voltage, split between buildings and levels, and metered flat by flat. The architecture is the architect's; our scope is the environmental clearance, IGBC and electrical design.

We prepared the load calculations in June and the electrical layouts in July 2026. Load: every flat at 75 W per sq m of carpet area and every showroom at 150 W, eighteen lifts, the domestic, drinking-water, flushing, sewage, pool and sump pumps, the water treatment plant and organic waste converter, basement ventilation of 95 kW and staircase pressurisation, street lighting, the amenities, stack parking and charging for 20% of the 631 car bays - 126 chargers of 7.2 kW - for 3,864 kW connected and 1,901 kW of maximum demand: 2,112 kVA, or 2,534 kVA with a 20% margin, on four 630 kVA transformers in their own room. Meters: 447 connections - 286 single-phase for the two-bedroom and MHADA flats, 155 three-phase for the larger flats, duplexes and showrooms, and 6 common - grouped on meter panels in a meter room for each wing. Backup: two 500 kVA DG sets for the lifts, pumps, ventilation, outdoor lighting and the lighting of every flat, and an 82.5 kVA set giving the showrooms full backup, each checked against the starting current of the motors. Distribution: four HT panels, four LT panels and changeover panels, the HT line in hume pipe, cable risers through the basements to each wing's meter room, and earthing for the HT panels, transformers, LT panels, DG sets, meter rooms, lifts and lightning arresters. Flats: a fixture layout and single-line diagram for the typical two- and three-bedroom flats - a 40 A main with a 30 mA earth-leakage breaker, an 18-way single-phase or 6-way three-phase board, risers of 6 sq mm up to the tenth floor and 10 sq mm above it to hold the voltage, AC, geyser and kitchen points, a video door phone and gas leak detectors - with the common lighting worked out from the lux levels each space needs.