A profitability index for rural biomass district heating systems evaluation

Biomass heating networks are an efficient and low-emission alternative for rural municipalities without natural gas supply. One of the main challenges for their implementation on a larger scale is to reduce the uncertainty in the profitability evaluation. The linear heat density is the index commonly used to evaluate the potential for heating networks investments. It provides highly accurate estimations in high-density building networks. However, it does not provide accurate enough evaluations for low-building-density networks, resulting in relevant deviations when applied to biomass district heating networks. This work proposes a new index to evaluate the profitability of biomass heating networks in rural environments based on the analysis of investment, operation, and biomass costs. It is developed based on the cost-benefit analysis of biomass heating networks. The new index has been applied to 499 rural municipalities in Spain, showing a high accuracy in estimating the profitability of investments, with R2 values between 0.8179 and 0.9442, compared to 0.2408 if linear heat density was used for the same cases. The analyses show the interest of this approach for the evaluation of biomass district heating potential in areas with dispersed populations.