# Explosives and propellants: Engineering and performance

Release rate, magazines and safety distances, not efficiency

Source page: https://www.materialinsights.org/energy/e_propellants/sg-eng/

What this tab covers Engineering and operating performance: round-trip efficiency, whether power and energy can be scaled separately, footprint and siting, and safety.

These stores are engineered for release rate and reliability; efficiency in the battery sense does not apply, and siting is dominated by separation distances and licensing.

#### Round-trip efficiency (energy release)
Unfavourable

There is no recharging, so round-trip efficiency does not apply. What matters is how much of the chemical energy does useful work, such as breaking rock or lifting a rocket. Blasting firms compete on blast design and electronic timing that get more useful work from each tonne; Orica, a large supplier, says its FY2025 margin growth came partly from greater uptake of premium products and advanced blasting technology (company statement).^[8](https://a.storyblok.com/f/329380/x/4267224ba0/orica-annual-report-2025.pdf)

#### Power and energy decoupling (release rate)
Mixed

Energy and power are fixed by the material and the device: detonation releases its energy in microseconds, and solid rocket motors burn at a rate set by their design. Liquid engines can be throttled, so power is set by the engine and energy by tank size, the closest these stores come to decoupling.^[7](https://www.energy.gov/sites/default/files/2021-10/new-lh2-sphere.pdf)

#### Footprint and siting flexibility
Unfavourable

Storage needs licensed magazines, separation distances from homes and roads, and controlled access. Cryogenic propellant stores are large: the new liquid hydrogen sphere at NASA's launch pad 39B holds about 4,700 cubic metres (1.25 million US gallons), versus 3,200 cubic metres for each Apollo-era tank.^[7](https://www.energy.gov/sites/default/files/2021-10/new-lh2-sphere.pdf)
 LC-39B LH2 sphere usable volume 4,732 m3 (1,250,000 gal)^[7](https://www.energy.gov/sites/default/files/2021-10/new-lh2-sphere.pdf) Apollo-era tank 3,218 m3 each^[7](https://www.energy.gov/sites/default/files/2021-10/new-lh2-sphere.pdf)

#### Safety and thermal runaway risk
Unfavourable

Accidental initiation is the defining hazard. Beirut's 2020 blast killed 218 people, wounded about 7,000, displaced more than 300,000 and caused USD 3.8-4.6 billion of physical damage (World Bank estimate). In the EU, the Seveso III major-accident directive applies to sites holding 10 t (lower tier) or 50 t (upper tier) of the most hazardous explosive classes. For ammonium nitrate the thresholds depend on grade: 10/50 t for off-specification material, 350/2,500 t for technical grade, 1,250/5,000 t for high-nitrogen fertiliser grade, and 5,000/10,000 t for fertilisers prone to self-sustaining decomposition.^[3](https://www.legislation.gov.uk/cy/eudr/2012/18/annexes/2012-07-04)^[4](https://www.hrw.org/report/2021/08/03/they-killed-us-inside/investigation-august-4-beirut-blast)
 Seveso III explosives (P1a) 10 t lower tier; 50 t upper tier^[3](https://www.legislation.gov.uk/cy/eudr/2012/18/annexes/2012-07-04) Seveso III ammonium nitrate from 10/50 t to 5,000/10,000 t depending on grade^[3](https://www.legislation.gov.uk/cy/eudr/2012/18/annexes/2012-07-04) Beirut 2020 deaths and damage 218 deaths; USD 3.8-4.6 bn physical damage^[4](https://www.hrw.org/report/2021/08/03/they-killed-us-inside/investigation-august-4-beirut-blast)

#### Sources

1. [Directive 2012/18/EU (Seveso III), Annex I](https://www.legislation.gov.uk/cy/eudr/2012/18/annexes/2012-07-04) legislation.gov.uk (EU directive text as adopted), 2012
2. ["They Killed Us from the Inside": an investigation into the August 4 Beirut blast](https://www.hrw.org/report/2021/08/03/they-killed-us-inside/investigation-august-4-beirut-blast) Human Rights Watch, 2021
3. [New LH2 sphere at LC-39B (Fesmire and Swanger, NASA Kennedy Space Center)](https://www.energy.gov/sites/default/files/2021-10/new-lh2-sphere.pdf) US DOE / NASA, 2021
4. [Orica Annual Report 2025](https://a.storyblok.com/f/329380/x/4267224ba0/orica-annual-report-2025.pdf) Orica Limited, 2025

## Other sections

- [Summary](https://www.materialinsights.org/energy/e_propellants/index.md)
- [Overview](https://www.materialinsights.org/energy/e_propellants/overview/index.md)
- [Correlation](https://www.materialinsights.org/energy/e_propellants/correlation/index.md)
- [Science and technology](https://www.materialinsights.org/energy/e_propellants/sg-sci/index.md)
- [Economics](https://www.materialinsights.org/energy/e_propellants/sg-econ/index.md)
- [Impact and additionality](https://www.materialinsights.org/energy/e_propellants/sg-impact/index.md)
- [What to track](https://www.materialinsights.org/energy/e_propellants/tracking/index.md)
- [Relationships](https://www.materialinsights.org/energy/e_propellants/links/index.md)