1. This sustainability problem is prevalent in both the energy and water sector. Traditional hydropower plants by use of steep dams or reservoirs or mountains use a lot of energy to use water to spin turbines and create electricity. It leads to high costs, and hard to scale ideas.

2. Name of technology: UK hills are being used as energy “batteries.”  

• Engineers are now developing a way to use hydropower to store electricity from slopes of small hills in replacement of dam walls and mountains.  This has led to an underground hydropower system which uses a mineral-rich fluid that has 2.5x the density of water to create the same amount of electricity from smaller slopes.

• The company that is rolling out this technology is called RheEnergise which said the project would pump fluid up a hill when there is low electricity demand. 

• Then it would be held in a storage tank until it is required to flow back down the hill, generating turbines, and returning the electricity used by pumps back to the grid. 

Source: https://www.theguardian.com/environment/2021/feb/08/powering-up-uk-hills-could-be-used-as-energy-batteries

3. Key stakeholders: 

• The investors for the program
• Chief executive of RheEnergise
• The UK energy sector  
• The engineering deployment team and ESIA (Environmental & Social Impact Assessment) specialists who need to ensure success of this project
• The wildlife trusts, environmental agencies, government, and other regulatory bodies that have stakes in the hills across the UK 
• Local community interest in using this technology to restore grasslands
• Potential industries that hope to partner with RheEnergise
• Other countries and other energy sectors could adapt and save costs from the success of this project 

4. First three steps: 

• First the chief executive of RheEnergise requires quicker and higher levels of investment to build this hydropower plant with consideration to engineering limitations and abiding by regulatory legislation.  
• Next, the company will need to start targeting various hillsides to locate where the projects could be most successful in order to market the idea and test it. 
• Last, this plant would have to be monitored and tested over an acceptable timeframe (60 years) to prove to local experts and local communities that this is the best alternative plan to harvest hydropower energy. Cost savings would have to be measured and compared to traditional methods.