Solar BESS mini project: send solar power to the grid at night
Our low-budget solar BESS stores 2.5–3 kW of daytime solar in a 51 V lithium battery and supplies about 13–14 units to the grid from 6 pm to early morning.
Solar power, now in the evening too
A normal on-grid solar system works only while the sun shines. It stops in the evening, just when homes in Kerala switch on lights, fans, TVs and mixers, and the KSEB grid needs the most power.
Our new solar BESS mini project (BESS means battery energy storage system) fixes this. It stores solar power during the day and sends it to the grid through the evening and night. It is a low-budget system, built so that ordinary households can afford it.
How it works: one full cycle every day
| Time | What the system does |
|---|---|
| Morning to evening | 2.5–3 kW of solar panels charge the 51 V lithium battery through an MPPT charger. In the day, the system only charges. |
| From 6 pm | The 1200 W BESS inverter starts sending stored power to the grid, when evening demand is highest. |
| Through the night | The inverter keeps supplying a steady 1200 W through the peak and off-peak hours. |
| Around 4–5 am | The battery reaches its set cut-off of about 40 V and the inverter stops, protecting the battery. |
| Next morning | The sun recharges the battery and the cycle starts again. |
The system at a glance
Why send solar power to the grid at night?
- It supplies power when the grid needs it most. Evening and night demand on the KSEB network is far higher than daytime demand. This system feeds the grid exactly then.
- Your solar works around the clock. The panels work in the day, the battery works at night, and nothing sits idle.
- It is affordable. A 1200 W inverter and a right-sized battery keep the cost low, so more families can take part.
- It runs by itself. Charging in the day and supplying at night happen automatically, every day.
Who is this for?
- Homes planning an on-grid system that also supplies power at night
- Families who want solar benefits on a small budget
- Homes with an existing rooftop system that want to add evening power
Good to know
- KSEB approval is needed. Any system that connects to the grid needs KSEB approval and a net meter. We help you with the paperwork.
- Output depends on the weather. The figures above are for a battery fully charged on a sunny day. On cloudy or rainy days the battery may not fill completely, and night-time output will be lower.
- Settlement follows KSEB rules. Units sent to the grid are recorded on your net meter and adjusted on your bill as per KSEB's current net metering rules.
- Correct sizing matters. We match the panels, MPPT charger, battery and inverter so the battery charges fully in the day and lasts through the night.
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