Green hosting: How Crazypatterns ensures measurably more sustainable infrastructure with Hetzner
Overview
- Why hosting matters for sustainability
- 1) 100% renewable energy – backed by certificates
- 2) Measurably efficient: Hetzner’s PUE vs. industry average
- 3) Saving water: air cooling – no water cooling
- 4) Circular instead of throwaway IT
- 5) Information security & transparency
- 6) Looking ahead: own solar parks
- Fact box (quick overview)
- Transparency note
- Sources (selection)
Crafting is resource-friendly – and our digital side should be, too.
Crazypatterns runs on Hetzner data center infrastructure. The following is documented: 100% renewable energy, PUE values of 1.10–1.16 (avg. 1.13), air cooling without cooling water, an average hardware service life of ~8 years, and ISO/IEC 27001 for the data center parks. All figures are sourced below (Hetzner).
Why hosting matters for sustainability
Data centers don’t just use electricity, but—depending on the cooling technology—also water. The Environmental and Energy Study Institute (EESI) gives a sense of scale: a mid-sized data center can require ~110 million gallons/year for cooling; very large facilities can reach several million gallons per day. Against this backdrop, water-free cooling is an important lever. (Environmental and Energy Study Institute)
1) 100% renewable energy – backed by certificates
Germany: Since 2008, Hetzner has sourced the electricity for its German data centers from hydropower; the NaturEnergie certificate confirms “100% hydropower” for 01/2023–12/2025 and quantifies a calculated CO₂ reduction of 77,000 t/year compared to the German electricity mix.
Finland: Since 2018, Hetzner has operated the data center park with renewable energy. For 2025–2026, a Vattenfall diploma “EPD Hydro” is available (hydropower). For 2024, an Oomi certificate documents “100% renewable: 50% hydropower / 50% wind”. (Hetzner)
What this means for Crazypatterns: Our hosting runs in data centers that are verifiably supplied entirely with renewable electricity.
2) Measurably efficient: Hetzner’s PUE vs. industry average
Hetzner reports PUE values of 1.10–1.16 for its data center parks; the Sustainability FAQs state an average of 1.13. According to the Uptime Institute, the global average in 2024 is PUE = 1.56.
How to interpret this: Compared with the global avg. (1.56), Hetzner’s total energy per IT watt is ≈ 27% lower (1.13 / 1.56 ≈ 0.72). The facility overhead (PUE–1) is 0.13 instead of 0.56 – ≈ 77% lower. (Definition: PUE = total energy / IT energy.)
3) Saving water: air cooling – no water cooling
Hetzner cools with outside air for up to 98% of the year and states that it uses only air for cooling (no use of water cooling; WUE note on the sustainability page). In the context of typical industry water consumption (see EESI above), this is a clear advantage for regions with scarce water resources.
4) Circular instead of throwaway IT
Hetzner develops and assembles its own servers, removes unnecessary components, optimizes airflow, and extends the service life to an average of ~8 years. Retired, tested systems are reused via the server auction; faulty components are repaired or recycled. In addition, waste heat is used to heat office/production rooms.
5) Information security & transparency
ISO/IEC 27001: The scope covers infrastructure, operations, and customer support for the data center parks in Nuremberg, Falkenstein, and Helsinki (company page + current FOX certificate). (Hetzner Datacenter)
Transparency: Hetzner is currently not climate-neutral and reports an avg. PUE of 1.13; a CSRD report under ESRS for FY 2025 has also been announced. (Hetzner Docs)
6) Looking ahead: own solar parks
Through HT clean energy GmbH, Hetzner is investing in photovoltaics. The first project—a solar park (~6.5 MW) in Nassau-Weikersheim on just under 7 ha—has been announced; in the long term, the goal is to supply the data centers with green power generated in-house. (Press release, trade reports.) (Hetzner)
Fact box (quick overview)
- 100% renewable energy: DE 100% hydropower (2023–2025); FI EPD Hydro (2025–2026), 2024: 50% hydropower/50% wind.
- PUE 1.10–1.16 (avg. 1.13) → ≈ 27% less total energy per IT watt vs. PUE 1.56 (global avg. 2024).
- No cooling water: air cooling, up to 98% free outside air.
- avg. ~8 years server lifespan, server auction, waste-heat use.
- ISO/IEC 27001 for the parks Nuremberg, Falkenstein, Helsinki (FOX certificate + data center page). (FOX certificate)
Transparency note
We deliberately don’t use the term “climate-neutral”. Hetzner states that it is currently (still) not climate-neutral; a CSRD/ESRS report for the fiscal year 2025 has also been announced. (Hetzner Docs)
Sources
- Hetzner – Sustainability: PUE range, 98% outside air, “no water cooling”, avg. lifespan ~8 years, energy origin DE/FI (with download links). (hetzner.com)
- NaturEnergie certificate 2023–2025 (DE): 100% hydropower, −77,000 t CO₂/year (vs. German electricity mix). (Link on Hetzner sustainability page)
- Vattenfall “EPD Hydro” 2025–2026 (FI): diploma for Hetzner Finland Oy. (Link on Hetzner sustainability page)
- Oomi certificate 2024 (FI): 100% renewable – 50% hydro / 50% wind. (cdn.hetzner.com)
- Uptime Institute Global Data Center Survey 2024: industry avg. PUE = 1.56.
- EESI – Data Centers and Water Consumption: industry context for water usage. (eesi.org)
- Hetzner – Data center / ISMS & certification: ISO/IEC 27001 including scope. (hetzner.com)
- FOX certificate (ISO/IEC 27001): current certificate for Hetzner. (PDF)
- Press release – HT clean energy (~6.5 MW solar park): Nassau-Weikersheim; goal: own generation. (hetzner.com)
- DataCenterDynamics (04/2025): context & assessment of the solar park. (datacenterdynamics.com)
Sources current as stated in the linked documents/pages: 11 September 2025.