The following open access publications give a broad overview of NETs:

Part 1: Research landscape and synthesis: https://iopscience.iop.org/article/10.1088/1748-9326/aabf9b

Part 2: Costs, potentials and side effects: https://iopscience.iop.org/article/10.1088/1748-9326/aabf9f

Part 3: Innovation and upscaling: https://iopscience.iop.org/article/10.1088/1748-9326/aabff4