Why do they need "a scientist" to compound statistics?

They certainly have BSc Mathematics types. What is the additional scientific discipline you think needs to weigh in here?

Your post doesn't have a reply link for some reasons but here is my response. What they need is expertise in energy generation. They need to understand concepts like a duck curve, power storage and its material requirements, relative EROEI of various power generation sources and a basic understanding of when newer forms of generation are likely to be ready. For instance, they should understand that renewables need to be well sited. They need to understand that the solar albino of Ireland is (far) too low for solar PV to be effective. Things of this nature. Engineering things around energy generation and the physics of how a grid works. If you don't understand these things, you are throwing darts at a dart board when you try to provide analysis of various types of industrial infrastructure.