frequently asked quesitons
Why is your material better for the environment?
Traditional featureless materials such as smooth concrete and granite provide little if any habitat enhancement. Frond matts and mattresses contain plastics and polypropylene that end up as microplastics and can enter the food chain. The rock used for rock dumping is often blasted out of mountains causing habitat damage and then transported large distances adding to a project’s CO2 footprint.
Existing concrete mattresses are deemed as marine litter under OSPAR and need to be recovered, cleaned and sent to landfill at great expense, several times the cost of the original purchase.
Reef Cubes® contain no plastics or other toxic materials. The structures we create have a specific pH and surface texture to maximise adhesion and settlement of marine flora and fauna. Our structures also have cavities that act as spawning grounds and protected nursery areas for juveniles.
Traditional Portland-based concrete production has a huge CO2 footprint, due to the high temperatures involved. Our activator contains no Portland cement and therefore has a CO2 footprint of less than 10% of traditional materials. We have recently achieved a carbon neutral mix and have plans for a negative carbon variant that can actually help offset a project’s CO2 footprint.
Where do you source your raw materials?
We aim to ensure traceability of all raw materials back to sustainable sources. At present the bulk of our material is from discarded sand and aggregate, a circular economy recycled resource from clay mining. Over 98% of our product is from circular economy sources. We have analysed materials from repurposed concrete mattresses and the building trade but have found them to be inconsistent in their composition and risk of contamination.
For pilot projects, we can manufacture all requirements at our Exeter site. Once demand increases, we anticipate manufacturing at a second site in Scotland. For projects outside of the UK, we aim to manufacture locally in-country and will source sustainably produced local materials to encourage the circular economy and minimise the project’s CO2 footprint. 75% of our mix is sand and aggregate and the remainder (primarily our proprietary activator) can be sent from the UK or manufactured locally if the project scale warrants this.
Will your products encourage more fishing?
The tracking patterns of trawlers already closely follow the distribution of pipelines and cables. There needs to be a step-change in compliance and regulation to police no trawl zones and respect marine protected areas (MPAs). The use of trawlable mattresses encourages such activity.
New legislation and drone/satellite tracking enforcement is coming, and we believe maximising the biodiversity and natural capital value of subsea asset protection will contribute to the recovery of fish stocks if these areas are respected and allowed to thrive.
Why partner with ARC Marine?
ARC Marine has been developing the technology since 2015 and was the Maritime UK start-up of the year in 2019. We have successfully moved from a research and development environment into pilot production and deployed 100+ 500mm units in April 2020. A number of other complex Reef Cube structures have been built and are awaiting deployment in Q4 2020.
We have carried out hydrodynamic testing, have patents granted in the UK and filed overseas. We have gained an MMO licence and pilot projects in aquaculture and offshore wind. Two of our directors have over 30 years of experience each in the energy sector.
What depths do your reef cubes® work too?
Marine life exists at all depths and so Reef Cubes® will have some benefit at any water depth. The sweet spot for their use is typically 10m to 50m when they are most likely to be quickly colonised and be used for nursery and spawning grounds.
At very shallow depths (<10m) wind/wave action is often more pronounced and so the small units may not always be suitable. Reef Cubes® are currently manufactured in sizes with sides from 150mm to 2m with weights from 5kg to > 6 Tonnes so this leaves plenty of options should a shallow reef be required.
Can Reef Cubes® be deployed using rock dumping vessels?
Yes, for Reef Cube® sizes up to 300mm. We have carried out dry drop testing onto the hard substrate from significant heights in the air recognising that this is more arduous than a deployment in water. We are awaiting grant funding to work with a major international deployment contractor on a fall pipe trial to prove their survivability from loading, through conveyors and into the fall pipe.
Larger Reef Cubes® can be deployed via tremie-pipe and side sweep rams. For the larger structures weighing over 6 tonnes, we are currently using block grabs and lifting frames.
How do your costs compare with traditional concrete marine products?
Our technology will be deployed in a similar way to traditional techniques so the deployment costs themselves should be directly comparable. This is a major contributor to their life cycle cost, typically being 4 times the capital equipment cost.
The life cycle cost of our mattresses will be significantly cheaper than traditional mattresses if they never have to be recovered – typically the cost to recover and send to the landfill is 4-5 times the capital equipment cost. We also carry out leachate testing and ensure strict traceability of all materials used unlike existing suppliers so it’s a higher quality sustainably produced product and we believe worthy of a premium.
How does this impact recovery of cables and pipelines?
If assets they are covering need to be recovered they can be moved to one side but our expectation is that both cables and cleaned pipelines will be allowed to stay in situ if there is an overwhelming environmental business case for them to remain and no financial driver to recover them for scrap value. It is noted that offshore wind tends to use aluminium and not copper base cables, so their recovery value is much less. Assets will be encrusted with a live reef and contribute to the ecosystem recovery sought.
NASA oceanographer Dr. Gene Feldman