What if gravity storage became mainstream? [26]

By -

Summary of the Article:

If gravity energy storage (GES) — beyond pumped‑hydro — scaled to mainstream adoption, power systems would gain a long‑lived, low‑degradation storage class that complements batteries and pumped storage across the 4–12‑hour band, with selective ability to stretch to multi‑day where topography, mine shafts, or rail grades are available. Early commercial proof points (e.g., Energy Vault’s 25 MW/100 MWh EVx in Rudong, China; ARES’s rail‑based GravityLine in Nevada; shaft‑based collaborations like ABB–Gravitricity) indicate that gravity platforms can provide fast ramping, frequent cycling, and long asset lives (30–40+ years) with minimal performance fade — provided civil/mechanical risks and permitting are well managed. [businesswire.com], [enlit.world], [new.abb.com]

Mainstreaming would require: (i) bankable RTE and LCOS at scale (target 70–85% RTE; LCOS converging toward ~$110–160/MWh in high‑utilization use cases); (ii) site archetypes (towers, rail grades, mine shafts) with standardized delivery and a matured supply chain; and (iii) market design that pays for multi‑hour firming, ramping and wind/solar curtailment capture. In this future, pumped‑storage hydropower (still >90% of global stored energy) remains the heavy artillery for deep, long‑duration shifting, while gravity systems fill non‑hydro geographies and brownfield niches with decades‑long durability. [hydropower.org]

1) The gravity storage landscape—what would be mainstream?

Three architecture families dominate the current pipeline:

  1. Tower‑based “block lift” systems. Energy Vault’s EVx lifts modular blocks; the Rudong (25 MW/100 MWh) unit achieved state grid interconnection in Dec‑2023, was tested and commissioned in 2024, and anchors a broader China pipeline (nine EVx deployments totaling ~3.7 GWh announced/underway). Claims include RTE >80% and 35‑year life; independent performance datasets will be key as operations mature. [businesswi...echina.com], [businesswire.com], [schweiz.biz]

  2. Rail‑based gravity (ARES). Electric locomotives move mass cars uphill to store energy and regenerate on descent. The Pahrump, Nevada GravityLine broke ground to provide 50 MW for ~15 minutes of regulation (a 5 MW demonstration is also referenced), with a design life targeted at ~40 years and no thermal runaway risk. Company materials and Sandia briefings indicate claimed RTE near ~90% under specific duty cycles; independent field data will be critical. [aresnorthamerica.com], [sandia.gov], [aresnorthamerica.com]

  3. Shaft‑based gravity (mine hoist / “GraviStore”). UK‑based Gravitricity, backed by an ABB collaboration leveraging 1,000+ installed mine hoists globally, targets >20 MWh per shaft with rapid response and no degradation; the model repurposes disused mine infrastructure for 50‑year service lives. A 250 kW demo has operated; feasibility work is active across Europe, India, and Australia. [new.abb.com], [energy-storage.news]

Takeaway: “Mainstream” gravity will not be one product — it will be a portfolio chosen by site: towers near load/VRE clusters, rail where ridgelines and rights‑of‑way exist, and shafts where mining legacies enable deep vertical drops. [aresnorthamerica.com], [new.abb.com]

2) Economics & performance—what changes if gravity scales?

Round‑trip efficiency (RTE). Peer‑review and vendor claims place GES RTE typically in the 70–85% band (architecture‑dependent), broadly comparable with many mechanical LDES options and, in some duty cycles, with pumped hydro; ARES has claimed higher values in specific designs. The physics audit of solid‑mass systems points to losses in hoists/motors, ropes/rigging, power electronics, and auxiliary loads; published analyses and NREL modelling for gravity platforms in grid‑regulation roles support viability assuming good mechanical design and controls. [ouci.dntb.gov.ua], [sandia.gov], [docs.nrel.gov]

LCOS trajectory. Early market research suggests first‑of‑a‑kind LCOS estimates for towers in the $180–260/MWh range, converging toward $110–160/MWh with manufacturing learning, high utilization, and optimized civil works — competitive for 4–12 h firming when battery capex or siting is unfavorable. Academic work on underground gravity (UGES/SGES) indicates very low energy inventory costs (sand/aggregate), with conceptual $1–10/kWh energy capacity costs and fleet LCOS in €7.5–15 ct/kWh depending on hoisting configuration and cycles; the swing factor is power equipment capex and duty cycle. [energy-solutions.co], [mdpi.com], [colab.ws]

Lifetime & degradation. A core gravity advantage is minimal energy fade over 30–50+ years versus lithium‑ion calendar/cycle degradation, shifting value toward capacity payments, frequency/ramping, and curtailment harvest rather than pure arbitrage. These claims are consistent with mechanical asset lives in hydro/rail/mining, though O&M on moving parts (bearings, ropes, brakes) must be proven at fleet scale. [new.abb.com], [aresnorthamerica.com]

Context vs. incumbents. Pumped‑storage hydropower (PSH) will still dominate deep storage; the IHA notes PSH accounts for >90% of the world’s stored energy, with a growing pipeline and rising annual additions. Gravity’s role is not to displace PSH, but to fill geographies where water/terrain/permitting limit PSH and where brownfield (mines, quarries, rail grades) make gravity faster to deliver. [hydropower.org]

3) System value—where gravity slots in if mainstream

Short‑to‑mid duration firming (4–12 h). Gravity provides high‑cycle daily shifting and fast response ancillary services without fuel or degradation penalties, absorbing mid‑day solar or night wind and firming evening peaks. This is exactly the interval where batteries are strongest today; gravity competes when battery costs/availability/land are constrained, or where very high cycling (>8,000 full cycles over life) erodes battery economics. [eia.gov]

Nodal/grid‑support roles. With synchronous motor‑generators and high‑inertia options, gravity plants can support frequency regulation and voltage control; NREL shows gravity motors’ inertias can be tuned for regulation services. Rail‑based and shaft‑based systems can be sited close to weak nodes, leveraging existing interconnections. [docs.nrel.gov]

Seasonal contributions. Not a core gravity niche versus hydrogen or PSH, but mine‑shaft designs with very low self‑discharge and cheap energy inventory (sand) can feasibly hold energy for extended periods, serving weekly/shoulder‑season gaps in the right locations. [mdpi.com]

4) Siting & permitting—how mainstream deployment would look

Brownfield‑first strategy.

  • Mines/shafts: Repurpose disused shafts (Europe, India, Australia) to avoid lengthy greenfield permitting and to defer shaft decommissioning costs; ABB–Gravitricity exemplifies the pathway from hoist engineering to grid‑compliant storage. [new.abb.com]
  • Rail grades / quarries: ARES sites near substations, quarries, or ridgelines, minimizing water footprint; early Nevada deployment targets a regulation product first to prove responsiveness and availability. [aresnorthamerica.com]
  • Towers near REZs: EVx colocates with wind/solar clusters (Rudong adjacent to wind farm), reducing curtailment and T&D congestion, and enabling local jobs (block fabrication from waste materials). [energy-storage.news]

Environmental footprint. Relative to electrochemical storage, gravity avoids fire/thermal runaway risk and can reuse materials (recycled steel, aggregate, mine infrastructure); lifecycle impacts hinge on civil works and materials. Peer‑review on gravity LCAs indicates competitive footprints vs. other mechanical storage when civil works are optimized. [aresnorthamerica.com], [colab.ws]

5) Policy & market design—what must change for gravity to scale?

Recognise gravity as LDES in planning. Current IEA tracking treats gravity as a small but emerging mechanical class alongside PSH, CAES, and flywheels; national and system operator plans should explicitly include gravity options in flexibility assessments and resource adequacy modelling, not just batteries and PSH. [iea.org]

Pay for capability, not only arbitrage. Revenue stacks must include capacity/adequacy, regulation/ramping, and congestion relief via long‑term contracts (e.g., cap‑and‑floor or availability‑based CfDs) that reflect long life/no degradation — similar to policy guidance for LDES and PSH. DOE/PNNL cost databases already include gravitational energy storage categories, signalling growing analytic treatment. [energy.gov], [pnnl.gov]

Brownfield fast‑track. Create permitting tracks for mine‑shaft reuse and rail‑grade projects with pre‑approved templates for safety, noise, and land use — akin to expedited pathways some jurisdictions use for closed‑loop PSH and substation‑adjacent BESS. This shortens time‑to‑revenue for first fleets. [hydropower.org]

6) Risks & mitigations at scale

RiskWhy it mattersMitigation
Civil & mechanical complexityTower erection tolerances, rope/hoist wear, braking systems; cost overruns erode LCOSEarly EPC standardization; vendor warranties on cycle counts; digital O&M; phased commissioning with regulation products first (prove availability). [energy-solutions.co]
Performance uncertaintyMarket needs bankable RTE/availability data; skepticism persistsPublish third‑party verified datasets from Rudong, Nevada, and shaft demos; NREL/Sandia benchmarking and test protocols. [businesswire.com], [sandia.gov]
Siting constraintsNot every node has shafts/grades/permitsPortfolio siting: shafts where mines exist; rail where grades and land are available; towers in industrial parks/REZs; standard siting playbooks. [new.abb.com], [aresnorthamerica.com]
Market under‑valuationEnergy‑only markets underpay LDESIntroduce LDES products (multi‑hour capacity, inertia/ramping credits) and long‑tenor offtake. Align with EU flexibility assessments and LDES policy momentum. [energy-storage.news]

7) A pragmatic scale‑up playbook (24–36 months)

  1. Prove bankability with three reference classes.

    • EVx tower: publish a year‑one operating book (RTE, availability, cycling, O&M) from Rudong; replicate at two new sites to show repeatability. [enlit.world]
    • Rail GravityLine: deliver Nevada fleet with certified response times and EIRP accuracy for regulation markets; document maintenance intervals for mass cars and traction systems. [aresnorthamerica.com]
    • Shaft GraviStore: complete a first commercial >10 MWh project via ABB partnership; formalize shaft selection and hoist refurbishment standards. [new.abb.com]

  2. Codify siting & safety templates. Issue model codes for towers/shafts/rails (braking redundancy, overspeed protections, rope inspection, public safety), drawing on mining/rail codes and hydro standards. [new.abb.com]

  3. Structure long‑tenor offtake. Blend capacity + regulation contracts (7–15 years) with availability KPIs and indexation; allow dual role assets that also offer industrial power quality or data‑center back‑up for extra revenue. [eia.gov]

  4. Localize manufacturing & supply chain. Standardize blocks, cars, hoists, drives; leverage recycled steel and local aggregate; train mine‑to‑storage workforce in regions with shaft potential (e.g., Central/Eastern Europe, India, Australia). [aresnorthamerica.com]

8) How the power mix evolves if gravity is mainstream

  • Batteries remain the workhorse for seconds‑to‑hours, peakers displace, and distribution‑level resiliency expands; cost curves continue to fall but land/safety and raw material considerations persist. [atb.nrel.gov]
  • Gravity fills the mid‑duration gap where daily cycling and long life trump efficiency, especially on brownfield sites; it arbitrages curtailment and provides ramping and inertia‑like services. [docs.nrel.gov]
  • Pumped hydro keeps the crown for deep storage; IHA’s 2024 outlook underscores PSH’s enduring dominance and growing pipeline. Gravity offers complementary geography and faster permitting options in many jurisdictions. [hydropower.org]

Net effect: A hybrid storage stack emerges — batteries for speed & ubiquity, gravity for durability & non‑chemical resiliency, PSH for depth — collectively delivering the firm, flexible backbone for high‑VRE grids. [iea.org]

9) What to watch (evidence that gravity is crossing the chasm)

  • Operational yearbooks from Rudong (EVx) and Nevada (ARES) with third‑party KPIs: RTE, availability (>95%), forced‑outage rates, O&M cost/MWh. [businesswire.com], [aresnorthamerica.com]
  • First >10 MWh shaft project FID under ABB–Gravitricity with published financing terms (debt/equity split, contracted revenues). [new.abb.com]
  • Independent LCOS benchmarks in DOE/PNNL or EU‑JRC updates that include gravity alongside batteries, PSH, CAES, flow — not just vendor claims. [pnnl.gov], [publicatio....europa.eu]

Bottom line

If gravity storage becomes mainstream, grids gain a durable, safe, and materials‑light storage class that scales through brownfield reuse (mines/rail/quarries) and modular new‑build towers. The business case hinges on proving bankable performance, standardizing civil/mechanical delivery, and securing long‑tenor revenue for multi‑hour flexibility. Do that, and gravity will sit comfortably between batteries and pumped hydro — not replacing either, but enabling a more resilient, lower‑cost path to 70–90% VRE systems. [hydropower.org], [iea.org]

Endnotes & references (selected, high‑quality)

  • State of gravity deployments: Energy Vault EVx (Rudong 25 MW/100 MWh) grid interconnection & commissioning; multi‑site China pipeline (~3.7 GWh). [businesswi...echina.com], [businesswire.com], [schweiz.biz]
  • Rail‑based gravity (ARES): Corporate disclosures and Sandia presentation (Nevada GravityLine, performance claims, siting). [aresnorthamerica.com], [sandia.gov]
  • Shaft gravity (Gravitricity) and ABB partnership: Press releases and sector coverage; mine‑hoist reuse and >20 MWh design intent. [new.abb.com], [energy-storage.news]
  • Role of pumped hydro (context): IHA 2024 World Hydropower Outlook — PSH >90% of global stored energy; pipeline growth. [hydropower.org]
  • RTE & LCOS evidence: Analytical studies of gravity RTE and loss mechanisms (Journal of Energy Storage, 2022); UGES economics and inventory costs (MDPI Energies, 2023); broader LCOS comparisons for gravity hoist systems. [ouci.dntb.gov.ua], [mdpi.com], [colab.ws]
  • Policy & tracking: IEA storage overview (gravity as emerging mechanical class); DOE Energy Storage Reports & Data hub; PNNL Cost & Performance database (gravity category included). [iea.org], [energy.gov], [pnnl.gov]
  • NREL analysis: Gravity systems for grid regulation (motor inertia and control). [docs.nrel.gov]

Comments

Post a Comment

Popular Posts

What is P50, P52 & P90 ?

By -
P52, P53 and P90 are terms often used in the renewable energy sector, particularly in the context of wind or solar energy production analysis. These refer to statistical probability levels used in energy yield assessments to estimate the expected production of renewable projects over a certain time frame. P50 : Represents the median or "best estimate" production scenario. It means there is a 50% chance that the actual energy production will be higher or lower than this value. It is the expected average production in a typical year. P52 or P53 : These are uncommon notations, but they might represent slight variations from the median estimate, with a slightly higher probability of occurrence than P50. P90 : This represents a conservative estimate, meaning there's a 90% chance that the actual production will be equal to or exceed this value, making it suitable for financial risk assessments. In summary, P-levels like P50, P52, or P90 provide different confidence levels for ...
Read more

BESS Tenders for Grid-Scale Energy Storage Adoption in India

By -
Introduction India’s energy landscape is undergoing a transformative shift. With over 50% of its installed power capacity now coming from non-fossil fuel sources—five years ahead of its 2030 target—the country is rapidly embracing renewable energy. However, the intermittent nature of solar and wind power presents significant challenges to grid reliability and energy dispatch. Battery Energy Storage Systems (BESS) have emerged as a critical solution to these challenges, and government-led tenders are playing a pivotal role in accelerating their adoption. Why Grid-Scale Energy Storage Is Essential India’s peak power demand surpassed 250 GW in 2024 and continues to rise. To maintain grid stability while integrating increasing volumes of renewable energy, robust energy storage solutions are essential. BESS enables: Load balancing  during peak and off-peak hours Frequency regulation  and grid stability Renewable energy dispatchability , ensuring power a...
Read more

GHG accounting and its emission factors

By -
Greenhouse Gas (GHG) Accounting involves quantifying emissions across different scopes (Scope 1, Scope 2, and Scope 3) and is typically guided by protocols such as the Greenhouse Gas Protocol. Here are the key formulas and approaches used in GHG accounting for each scope: 1. Scope 1: Direct Emissions Scope 1 includes direct emissions from sources owned or controlled by the organization (e.g., fuel combustion in company-owned vehicles, emissions from manufacturing processes). Formula for Combustion Emissions For fossil fuel combustion: Emissions = Activity Data × Emission Factor \text{Emissions} = \text{Activity Data} \times \text{Emission Factor} Emissions = Activity Data × Emission Factor Activity Data : Quantity of fuel used (e.g., liters of diesel, cubic meters of natural gas). Emission Factor : A coefficient that represents the emissions produced per unit of activity (e.g., kg CO₂ per liter of diesel). Example (CO₂ emissions from fuel): CO₂ Emissions = Fuel...
Read more

Deviation Settlement Mechanism (DSM) guidelines 2024

By -
As per the latest Deviation Settlement Mechanism (DSM) guidelines from the Central Electricity Regulatory Commission (CERC), DSM charges are defined based on grid stability needs, particularly regarding frequency deviation and renewable energy dynamics. The charges vary depending on the deviation percentage from the target frequency range (49.90 Hz to 50.05 Hz), with penalties scaling for larger deviations. For renewable-rich and super renewable-rich states (based on their installed wind and solar capacity), CERC allows greater flexibility in permissible deviation limits on the demand side. This aims to balance the grid challenges posed by variable renewable generation. States with renewable capacities between 1 GW and 5 GW are considered renewable-rich, while those with over 5 GW are super renewable-rich. Stand-alone energy storage systems (ESS) are subject to similar DSM charges as general sellers, but ESS paired with renewables like wind and solar follow specific volume limits for o...
Read more

Why the dislike button is removed in all the social media platforms?

By -
 The removal or absence of a dislike button on most social media platforms can be attributed to several reasons, primarily centered around user experience, mental health, and the dynamics of online interactions. Here's a detailed explanation: 1. Preventing Negativity and Harassment A dislike button could encourage negative behaviors, such as trolling or bullying. Users might use it to target individuals or content creators, leading to a toxic environment. Platforms aim to promote constructive engagement rather than actions that might demoralize users. 2. Mental Health Concerns Social media companies are increasingly aware of the impact their platforms have on mental health. Visible indicators of disapproval could harm users' self-esteem and lead to stress or anxiety, especially for younger or vulnerable audiences. 3. Focus on Constructive Feedback Platforms encourage users to give feedback in a constructive manner, such as through comments or reporting inappropriate content. A...
Read more