01 / Why nowSustainability is now an economic question
Three forces have converged. Energy is the largest operating cost of a data centre, so efficiency is money. Carbon is now reported, scrutinised and increasingly regulated. And AI has put data centre energy use firmly in the public eye.
The levers that cut carbon are largely the ones that cut cost: efficiency and sustainable supply.
Energy is the big cost
Power dominates data centre operating cost. Shave PUE, run warmer and buy energy better, and the savings compound every hour of every year.
Carbon is reported now
Scope 2 emissions, from the electricity you buy, sit in ESG reports and customer due diligence. 100% sustainable supply addresses them directly.
Regulation is tightening
The EU Energy Efficiency Directive and CSRD are bringing mandatory efficiency reporting and disclosure to data centres. It is better to be ahead of them.
AI raised the stakes
Rising AI power demand has made efficiency and clean supply a reputational issue as well as an operational one. Buyers and regulators are watching.
02 / Efficiency firstThe levers we build in
The greenest kilowatt is the one you never use. Before the question of where energy comes from, a hall’s design and build decide how much of it is wasted. These are the efficiency levers we engineer into every project, and they cut the bill as much as the carbon.
- 01
Airflow and containment
Hot and cold-aisle containment, blanking and sealing stop supply and exhaust mixing: the cheapest, highest-return efficiency win, letting a hall run warmer and chill less.
- 02
PUE-led design
We design for low PUE from the start, through airflow, cooling strategy, free cooling and liquid-readiness, not as an afterthought once the kit is in.
- 03
Free and liquid cooling
Warm-water and free cooling cut or remove mechanical chilling, and liquid cooling pushes PUE towards ~1.1 and opens the door to heat reuse.
- 04
Local, low-carbon kit
We specify sustainable products and source them as locally to site as possible, cutting the embodied carbon and transport emissions built into a project before it ever powers on.
- 05
Right-sized, with headroom
Modular, phased fit-out means you power and cool what you are actually using, with no stranded capacity burning energy for racks that are not there yet.
- 06
Measured, not assumed
Metering and DCIM make efficiency visible. You can only improve PUE and WUE if you measure them and act on the numbers.
03 / The overheadWhere the energy goes
PUE is total facility energy divided by IT energy. Everything above 1.0 is overhead: cooling, power conversion, lighting. Move the slider to see what that overhead means for a hall with a steady 1 MW of IT load, across the 8,760 hours of a year.
Arithmetic only: facility draw = IT load × PUE; overhead a year = IT load × (PUE − 1) × 8,760 h. The industry average of 1.56 is from the Uptime Institute (2024).
04 / The energy itself100% sustainable energy, at a better rate
Once a hall is efficient, the biggest single carbon move is the supply itself: switching to 100% sustainable energy. The assumption is that green costs more. Bought well, it often costs less, and that is what we help clients do.
A specialist broker, working for you
Through our partnership with Europe’s leading data centre energy broker, we help clients secure 100% sustainable energy at very competitive rates, with the buying power and market knowledge of a specialist.
Across EMEA
We support clients securing sustainable supply across the UK, Europe and the wider EMEA region, matched to where the sites actually are.
Lower bills and lower carbon
In 2025, several of our data centre clients renewed at a lower rate while moving to fully sustainable supply, cutting cost and emissions in one contract.
Scope 2, directly
Sustainable purchased electricity is the most direct lever on Scope 2 emissions: a fast, evidenced step towards net-zero and ESG goals.
Tell us roughly what you use and what you pay, and we will come back with an indicative view of a better, greener offer.
05 / Your numbersGet a better, greener energy offer
Set roughly what you draw and what you pay today. We will use it to prepare an indicative, no-obligation view of 100% sustainable supply at a competitive rate, and where the savings could sit.
Drag the sliders, add your details, and we will be in touch with an indicative offer. Your figures are only used to prepare it.
Thanks — that’s through to our energy team. We’ll be in touch with an indicative 100% sustainable offer based on your figures.
Indicative only. A real offer depends on your site, load profile, contract timing and the market on the day. The calculator assumes round-the-clock draw (kW × 8,760 h); actual consumption varies with utilisation.
06 / The metricsWhat gets measured and reported
Sustainability claims have to be backed by numbers. These are the metrics and frameworks buyers, auditors and regulators increasingly ask for, and that a well-run, efficient hall can answer with confidence.
- PUE
- Power usage effectivenessTotal facility energy divided by IT energy. The headline efficiency number: about 1.5 is legacy, about 1.1 is best in class.
- WUE
- Water usage effectivenessIncreasingly scrutinised alongside energy, especially where evaporative cooling is used. Designed for, not assumed.
- Scope 1/2/3
- Greenhouse-gas reportingSustainable electricity cuts Scope 2; local, low-embodied-carbon kit reduces Scope 3.
- EED / CSRD
- Regulation and disclosureEU efficiency and disclosure rules, plus corporate net-zero commitments, are turning good practice into reporting obligations.
07 / How Optronix helpsCutting cost and carbon from both directions
We help clients reach their net-zero and ESG goals, and cut energy cost, from two directions at once: efficient design and build, and 100% sustainable energy supply at competitive rates. From white-space design through to operations, sustainability is built into how we work.
100% sustainable supply at a competitive rate
Through our partnership with Europe’s leading data centre energy broker, we help you move to fully sustainable supply, cutting Scope 2 emissions and cost together. Start with the calculator above.
Efficiency engineered in from day one
Airflow and containment, PUE-led design, free and liquid cooling, and sustainable products sourced as locally to site as possible, so low energy use and low embodied carbon are designed in.
Related
Sustainability
Cut energy cost and carbon together.
Use the calculator above for an indicative green-energy offer, or talk to us about designing and building a more efficient hall, new or retrofit.
Sources and notes
- Optronix sustainability offering: 100% sustainable energy at competitive rates through a partnership with a leading data centre energy broker; 2025 client renewals at lower rates on fully sustainable supply.
- Efficiency metrics: PUE and WUE per The Green Grid; greenhouse-gas Scopes 1, 2 and 3 per the GHG Protocol. Industry average PUE of 1.56 from the Uptime Institute global survey, 2024.
- Regulatory context: the EU Energy Efficiency Directive (EED) and the Corporate Sustainability Reporting Directive (CSRD); ASHRAE thermal guidelines for efficient operation.
General guidance; calculator output is indicative, not a quotation. Consumption and spend are estimated from a constant-draw assumption (kW × 8,760 h) and the figures you enter; actual usage, rates and any offer depend on your site, load profile, contract and the market. Submitted figures are used only to prepare an indicative energy offer.