Navgathi on a strong foundation of solar installation on boats turned towards land based installation. The first test case was the computer UPS system in Navgathi office. A suitable grid-tie inverter was selected; however to utilize the solar energy during grid outage a relay system with charge controller that works under this scenario was proposed. This ensure that all the energy produced by the solar panels can be utilized.
Solar Panels installed on roof of Navgathi office
[box]Scenario Before Installation[/box] The office computers, 15 in number in one floor, were powered through in-line UPS (Liebert 3 kVA), that ensures un-interrupted power supply when KSEB (State Electricity Board) grid fails. The overall consumption of the office top floor was around 40 units per day including air-conditioners and other loads.
The objective was to reduce this electricity consumption by means of solar installation. Since most of the consumption is in day-light hours (8:30 AM – 6:00 PM) and that we had a dedicated UPS for computers and lights/fans, it made sense to install grid- tie system without batteries.
[box]First Stage: Grid-tie Inverter[/box]
We experimented on the angle of the solar panel installation. Initially we placed then horizontally and noted the power generation. Once the structure was completed for placing them at 10 degrees South facing, the energy produced increase by 25%. On a average we could generate 19 kWh in a day (February in Kochi).
Solar Panels: 17 panels of 230 W each = 3910 W
Grid Tie-Inverter: 3000 W
Make: SMA Sunny Boy 3000 TL
Make: Midnite Solar
Relay & Controls: In-house
The system give the following benefits:
- Drastic reduction in electricity bill
- Increased back-up time of UPS in the day time (when is grid fails)
- Complete utilization of solar energy from panels
All equipments, cable, junction box etc. are IEC approved.