Commercialising Napier Grass as an Alternative Biomass Feedstock

During the 2017 trials of the 32 MW biomass power plant at the Sunbird Bioenergy Mabiifu project site, it was established that the local wild napier grass (colloquially elephant grass, or scientifically Pennisetum purpureum) is an excellent alternative biomass feedstock to bagasse. Since then, the agronomy team have been working to introduce napier grass as a commercial and sustainable crop on the estate.

The first phase is to establish a nursery to cultivate the seeds and monitor their growth in a controlled environment. The senior agronomist have recruited local workers who are being trained to manage the nursery.

A selection of different varieties of napier grass have been sourced from numerous sources across Africa and South East Asia, and will be be trailed on the estate to asses their yield and growth characteristics. The first critical task is to ensure the seedlings are potted within 24 hours of arriving in the country.

After successfully potting the seedlings, they are left in a warm environment to germinate.

Additionally, local elephant grass cuttings have also been taken, and have been potted. These will act as a baseline to compare the performance of the new seedlings against the local wild growing grasses.

After germination, the plants have been moved out doors. A canopy has been erected to shield the young plants from the direct sunlight.

The newly recruited nursery team continue to look after the young plants, and will transplant them into the fields in approximately 3 months time. This has provided a good opportunity to transfer skills to the local rural farmers ass part of our Farmer Development Program (FDP). Typically, local rural farmers farmers have limited access to improved varieties of planting materials and consequently their yields are far lower than international averages. This project provides education on how to multiply out improved varieties, which can be applied to their own farms.

Sunbird Bioenergy General Manager, Bheki Chatira, closely monitors the new napier grass nursery and team.