Prima Klima PK125-TC is highly efficient temperature controlled duct fan. It's meant for moving air in or out of houses and for that it is really low noise (compared to more industrial models)
I use it in my Data center to move the hot air on the back of the servers in to my house. To save on heating.
Link US - Temperature Control duct fan : https://amzn.to/2qyffDN
Link UK - Prima Klima PK125-TC : https://amzn.to/2qz3ihI
Even just 1$ a month, comes out to the same as Binge-watching all of my 500+ Videos every month.
My PlayHouse is a channel where i will show, what i am working on. I have this house, it is 168 Square Meters / 1808.3ft² and it is full, of half-finished projects.
I love working with heating, insulation, Servers, computers, Datacenter, green power, alternative energy, solar, wind and more. It all costs, but I'm trying to get the most out of my money, and my time.