The repowering of vertical axis water mills preserving their cultural heritage: techno-economic analysis with water wheels and Turgo turbines

Purpose – The paper presents a techno-economic analysis of the repowering of traditional vertical axis water mills (VAWMs) to help investors, mill owners, engineers and policy makers to preliminary estimate related benefits and costs of a VAWM repowering. Method - Two sustainable repowering solutions were examined with the additional aim to preserve the original status and aesthetics of a VAWM: the use of a vertical axis water wheel and a vertical axis impulse turbine. The analysis was applied to a database of 714 VAWMs in Basilicata (Italy), with known head and flow. Findings - Expeditious equations were proposed for both solutions to determine: 1) a suitable diameter as a function of the flow rate; 2) the costs of the electro-mechanical equipment; 3) achievable power. The common operating hydraulic range of a VAWM (head and flow) was also identified. Reality checks on the obtained results are shown, in particular by examining two Spanish case studies and available literature. The power generated by the impulse turbine (Turgo type) is twice that of a vertical axis water wheel, but it is one order of magnitude more expensive. Therefore, the impulse turbine should be used for higher power requirements (> 3 kW), or when the electricity is delivered to the grid, maximizing the long-term profit. Originality - Since there is not enough evidence about the achievable performance and cost of a VAWM repowering, this works provides expeditious tools for their evaluation.

QUARANTA Emanuele;  PUJOL Toni;  GRANO Maria Carmela; 

2023-05-02

EMERALD GROUP PUBLISHING LTD.

JRC124978

2044-1266 (online),   

https://www.emerald.com/insight/content/doi/10.1108/JCHMSD-03-2021-0040/full/html,    https://publications.jrc.ec.europa.eu/repository/handle/JRC124978,   

10.1108/JCHMSD-03-2021-0040 (online),