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We are passionate about building a sustainable future

"We aim to protect the environment as well as enrich our wider community through the support of clients, those living locally and through charitable foundations. Our efforts have been recognised as winners of the Green Data Centre accolade at the Datacentre Leaders Awards."

Custodian's Corporate Social Responsibility

Our green story so far...

We believe that data doesn't have to cost the earth.


Data centres consume incredible amounts of energy, so we wanted to go about things in a different way.

As a data centre, we've built the environment into our core from day one. We have designed our infrastructure and processes to minimise impact on our natural resources, thus optimising our efficiencies and achieving unprecedented levels of energy conservation without our industry.

It all started with our cooling systems.


We use five times less energy per kW of IT load than the average data centre.

Through our radical fresh-air cooling system, which won us Green Data Centre of the Year in its first year of operation, and evaporative cooling systems, our PUE (Power Usage Effectiveness) regularly drops below 1.2, meaning that for every 1kW used to power equipment hosted in the data centre, we use 0.2kW of power to operate all related areas of infrastructure, such as cooling, lighting etc.

These efficiencies not only allow us to benefit the surrounding environment, but also allow us to pass the cost-savings on to our clients; maintaining resilience and 100% power uptime since we first switched the power on.

We achieve this efficiency in a number of ways. For 100% of the year, the data centre utilises fresh air cooling, brought in from outside and filtered to clean room standards to eliminate contamination, passing into the data centre via a bank of multiple fans. In the event that British temperatures soar beyond a set threshold, the evaporative system comes online.

A reverse osmosis plant purifies water which the system then uses to produce a very fine mist. Within a large chamber, this moisture is used to raise the humidity of the slow moving air which passes through, decreasing its temperature. The evaporative system also acts as a room humidifier, and is supported by dual water mains, ensuring that it is resilient against mains failure. This approach is 2N resilient, with completely separate duplicate systems protecting against failure should one element be affected by outage or technical difficulty.

The only colocation provider in the world to show its efficiency live online.


As far as we are aware, no other facility shows their PUE live, like us, below.

PUE is the ratio of how much energy is used by the facility and its infrastructure against the IT load. A Data Centre's PUE is calculated by: Total DC Energy Use / IT Equipment energy use = PUE. A PUE of 1.0 is perfect, but not feasible in the real world. The average PUE for most data centres is 2.0, which means that for every 1kW of IT load, they use another 1kW for cooling, electrical losses etc. The following graph is a live feed of our Kent Data Centre's PUE.

Live PUE Graph

Step inside a green data centre cooling system

Follow Pav, our Head of Infrastructure, as he shows you around our evaporative cooling system at our Kent data centre.

For 95% of the year, the data centre utilises fresh air cooling, brought in from outside and filtered to clean room standards to eliminate contamination, passing into the data centre via a bank of multiple fans. In the event that British temperatures soar beyond a set threshold, the evaporative adiabatic system comes online.

Further adding to its green credentials, the heat produced as a by-product of the extraction system is recycled within the site of the Maidstone Television Studios, where Custodian is based.

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Our corporate social responsibility


We are inspired

"...tree planting is a climate change solution that doesn't require President Trump to immediately start believing in climate change, or scientists to come up with technological solutions to draw carbon dioxide out of the atmosphere. It is available now, it is the cheapest one possible and every one of us can get involved. Individuals could make a tangible impact by growing trees themselves, donating to forest restoration organisations and avoiding irresponsible companies."

Prof. Tom Crowther
Swiss University ETH Zurich

At Custodian, we've taken this into our own hands, beginning our very own tree building scheme on a plot of land owned by us in the heart of Kent.

As trees grow, they will absorb and store carbon dioxide emissions that are driving global heating. Over the course of 2020, we'll plant hundreds of trees in a mission to offset our carbon and tackling the climate crisis.

The team of employees will work together to make this happen, so watch this space as we video and document our journey. Subscribe to our YouTube channel today.

Work with the Kent Wildlife Trust and BEN

Custodian have been longstanding supporters of the Kent Wildlife Trust and their aims of protecting and restoring habitats in our home county, Kent.

In 2019, the Trust began putting together the Business Environment Network (BEN), which aims to bring together businesses in Kent to discuss sustainability, corporate social responsibility, climate change and much more.

Since then, Custodian has taken on the role of being a key part of the steering group. This group will continue driving events discussing these important topics in our group efforts to protect the environment.

Our team will continue to share our knowledge of sustainable building, providing insight and information on our green cooling technologies and overall corporate social responsibility drive.

Kent Wildlife Trust logo

Kent Wildlife Trust