Lighting and efficiency in your indoor grow

Lighting is the main energy consumer in any indoor grow, much more than fans or ventilation. Optimizing your lighting setup is the most effective way to reduce power use while maintaining high yields. Here are the 5 key factors:

  1. How to light up an indoor grow efficiently
    Modern homegrows rely on LEDs instead of HPS. But efficiency isn’t just about the number on a datasheet. Spectrum, PPFD and even light distribution have a big impact on energy savings and plant performance.

  2. Electrical efficiency from a modern LED grow light
    The most efficient LEDs produce more plant-usable photons with less power. Look for lights that deliver high output with low energy consumption. That’s the key to real efficiency.

  3. Quantum efficiency and the right spectrum
    Not all light is equal. Red and blue light are most efficient for photosynthesis, especially at lower intensities. For fruiting plants, higher PPFD with a full spectrum works best.

  4. The right light intensity
    Trials show:

    • 700 µmol/m²/s = best efficiency per watt

    • 900 µmol/m²/s = best balance for homegrows

    • 1100 µmol/m²/s = max yield per area (when space is limited)

  5. Light distribution is key
    Uniform light ensures all plants grow evenly and use nutrients efficiently. Hotspots waste energy. A well-balanced light spread is just as important as intensity.


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