@CloudyMrs There's this from 2021 about their energy use: https://www.thisismoney.co.uk/money/bills/article-9325319/Royal-Family-spends-2-5m-energy-bills-year.html
And obviously things have changed for them since 2020, but there's this assessment of their carbon footprint: https://www.theecoexperts.co.uk/blog/royal-family-carbon-footprint