Technology

At Q Energy, we are exploring various technologies that utilise the unique characteristics of underground spaces for large-scale energy storage.

Storage

Underground gravity storage technology uses the power of gravity to offer some of the best characteristics of lithium batteries and pumped hydro storage.

Ideally suited to network-constrained users and operators, distribution networks, and major power users, our technology operates in the 1 MW to 20 MW power range and enables existing grid infrastructure to go further in a renewable energy world.

Key features:

  • With no cycle limit or degradation

  • Zero to full power in less than a second

  • Can run fast to deliver high power, or more slowly for a longer duration.

  • Levelised costs are well below those of lithium-ion batteries.

These special characteristics mean Q Energy’s gravity energy storage is ideally suited to the following use cases:

Grid services. Delivering power to distribution and transmission network operators (DNOs and TSOs) for grid balancing and frequency regulation, allowing them to ensure quality and security of supply with a technology designed to last for decades.

Co-location. By coupling gravity storage with large scale renewable generation at the same site, solar farm owners and operators can time-shift solar supply to high price peak periods, reduce connection costs, and stack revenue streams.

Industrial decarbonisation. On-site energy storage can support industries including mining, oil and gas, and data centers to decarbonise their operations by reducing grid demand, increasing the resilience and reliability of supply, and delivering ancillary service income.

Energy access. Gravity storage can be designed into mini grids, allowing utilities and minigrid developers to reduce infrastructure spend and deliver better energy access to rural and off-grid communities, especially during non-daylight hours.

Key features:

Storing hydrogen underground reduces the risk of leaks and protects the storage container from damage.

Store up to 100 metric tonnes of compressed hydrogen per shaft, with the option to have multiple shafts on one site.

Surrounding geology helps contain pressure and reduce storage costs.

H2 Flexi Store technology is ideally placed to meet the growing demand for green hydrogen in the following use cases:

Existing uses. Hydrogen production by electrolysis will replace existing carbon-emitting production techniques for applications such as ammonia and methanol production.

High grade heat. Hydrogen is the only low-carbon way of reaching the temperatures needed in numerous industrial processes.

Grid-scale energy storage Electrolysis of water can generate hydrogen from otherwise curtailed renewable generation, providing GW-scale storage for daily peaks, long durations, and inter-seasonal requirements.

Shipping and aviation The growing requirements of shipping and aviation will drive the growth of green hydrogen production.

Hydrogen Storage 

H2 Flexi Store's underground hydrogen storage technology uses the geology of the earth to safely store large volumes of green hydrogen. Purpose-built shafts can be built wherever required to offer long-term storage close to the point of demand.

Storing hydrogen in underground shafts is intrinsically safer and less obtrusive than above-ground options, and unlike salt caverns, it is not restricted to deployment in areas with particular geologies.

Multi-Weight Project

“Multi-Weight” Storage System

The project will deliver up to 4 MWh of electricity storage and demonstrate the ability to deploy systems that use multiple weights (lowered one after the other with consistent power output) in new purpose-built shafts to store energy and provide grid balancing services.

By using multiple weights, the system is able to greatly increase energy storage capacity through the increased mass in the system without the need for multiple complex winch systems.  

Underground Hydrogen Storage: Feasibility Study

Studies are ongoing and progressing to the feasibility of purpose-built underground shafts where gravity storage could be combined with hydrogen and inter-seasonal heat storage.

Moving forward to Phase 2, is where the partners would build a multi-million-pound scale demonstrator in the UK.

This would involve sinking a purpose-built, concrete-lined vertical underground shaft with a domed cap to create a demonstration pressurised hydrogen storage vessel.