Technology
Energy storage is the fundamental element of the new energy system
CHALLENGE – As the world generates more electricity from intermittent renewable energy sources, there is a growing need for technologies which can capture and store energy during periods of low demand and release it rapidly when required.
SOLUTION – At Gravitricity we are developing two complementary technology streams which utilise the unique characteristics of underground spaces to provide an appropriate scale of distributed energy storage.
Our technology epitomises our engineering philosophy:
High reliability
Long life
Resilience
GraviStore – Gravity Power Storage
Uses existing mineshaft to support 1,000s of tonnes of mass to store electricity
Our GraviStore underground gravity energy storage technology uses the force of gravity to offer some of the best characteristics of lithium batteries and pumped hydro storage.
Key advantages of underground gravity energy storage
50+ year life
With no cycle limit or degredation
Fast response time
Zero to full power in less than a second
Versatile operation
Can run fast to deliver high power, or more slowly for longer duration
Lower costs
Levelised costs below lithium-ion batteries
Efficient
No standing losses
Modular
System design gives ability to relocate or reconfigure
Ability to repurpose valuable assets:
Extends life of existing infrastructure
Maintains communities
Makes use of embedded costs / saves decommissioning costs
Re-uses grid connections
GraviStore Advantages
Reliability, resilience and longevity
Economics
- Long life (>50 years, >50,000 cycles)
- Competitive LCOS
Performance
- Rapid response (<1s) for high value markets
- High efficiency (~80% round trip efficiency)
- Versatile energy / power ratio (15 mins – 8 hrs)
- No depth of discharge limits
- High power output without degradation
- Very high availability (97%)
- No standing losses
Implementation
- Security of supply – limited exposure to geopolitical risks
- Small physical footprint
- No combustible chemicals
H2FlexiStore – Hydrogen Storage
Distributed mid-scale buffer storage for Green Hydrogen
Our H2FlexiStore underground hydrogen storage technology uses the geology of the earth to contain pressurised fuel gas, allowing safe, large-scale storage underground, close to the point of demand.
Key advantages of underground hydrogen storage
Safe
Storing hydrogen underground reduces the risk of leaks and protects storage container from damage
Flexible capacity
Scalable to 100 tonnes of H2 per shaft. Modular design
Location flexibility
No need for limited geological conditions, such as salt caverns. A distributed system which stores hydrogen where it is needed
Lower costs
Competitive capital cost and low running costs
Small footprint
Reduced surface area compared to above ground compressed hydrogen storage
50+ year life
With no cycle limit or degradation
Flexible design:
Enables safe, large-scale storage
Provides green hydrogen at the point of use
Utilises our underground expertise
Allows for a reduced/minimal above ground footprint
H2FlexiStore Advantages
Economics
- Long life (>50 years, 18,000+ cycles)
- Competitive system cost
- Containment method prevents microbial contamination and hydrogen consumption seen in underground geological storage
USPs
- Intermediate scale buffer store
- 40x smaller footprint than equivalent above storage for 65 tonnes
- Uses 6x less steel than equivalent above storage for 65 tonnes
(equates to £46 million of additional steel alone)** - Distributed storage provided at the point of use
(reduced infrastructure build out costs) - Removes vulnerability of above ground storage
- Multi-layer containment
- Compact balance of plant
Implementation
- Fast deployment
- Greater safety leading to smoother public acceptance
How do we compare?
GraviStore
High round trip efficiency for ES
Leading asset life on energy storage technologies – in years
H2FlexiStore
Need for industrial scale mid-capacity storage
60,000 gas bottles
at 300 bar and 20°C requiring 4,500m3
10 kilometres of underground pipeline at 85 bar and 20°C requiring 15,000m3
1/3 of a salt cavern at 45 bar and 20°C requiring 70,000m3
Market Use Cases
GraviStore
H2FlexiStore
