The key focus areas for ensuring sustainable design in the data centre domain include:

  • Power management: Bringing greater efficiency/reliability/lower cost of ownership.
  • Capex-opex: Balancing the risk between capital expenditure and operating expenditure.
  • Flexibility: Building a solution that is expandable as per market requirements.
  • Standardisation: Incorporating procurement and frequency modulation efficiencies with innovation in design.
  • Target savings: Saving on the opex of mechanical, electrical and plumbing (MEP) services (which make up around 40 per cent or more of the entire opex).
  • Reduced construction time: Spending a month in design to save three months on programming.
  • Power usage effectiveness: Increasing the levels of efficiency at design peak.

Use of renewable energy

Renewable energy can be integrated into cooling systems, either directly or through grid connections. Hybrid systems can combine renewable sources with energy storage or backup generators for reliable and sustainable cooling.

India’s energy trend is shifting towards renewable sources, with a global PPA trend. However, many data centre companies do not prefer on-site installation, making it challenging to achieve this goal. Some of the challenges faced while using renewable energy are intermittency, cost, and infrastructure and policy. These issues can be addressed by:

  • Intermittency: Adopting storage technologies such as batteries or grid balancing solutions.
  • Cost: Decreasing costs of renewable technologies make them increasingly competitive with traditional energy sources.
  • Infrastructure and policy: Investments in renewable infrastructure and supportive policies facilitate widespread adoption.

Zero liquid discharge

Zero liquid discharge (ZLD) is a water treatment process that eliminates liquid waste by recovering all wastewater for reuse and leaving zero discharge at the end of the treatment cycle.

Indian developers’ and global interest in ZLD is growing, with solutions being increasingly implemented in the data centre industry. However, high costs can be a challenge. Balancing costs and ensuring cost-consciousness is, therefore, crucial.

However, challenges include high initial investment, operational costs, complex system design and maintenance, energy-intensive processes such as evaporation and crystallisation, and the need for expertise in water treatment and management.

Rainwater harvesting

The government has mandated the installation of rainwater harvesting systems to meet water and emission requirements. Despite some resistance to innovative ideas, the government is actively working to promote sustainable practices and meet water and emission requirements.

These systems capture and recharge groundwater strata, while storing and reusing rainwater for domestic and industrial purposes.

Air-cooled vs water-cooled

Air-cooled systems: They use fans and fins to dissipate heat from equipment through air circulation. They require minimal to zero water usage for cooling, relying on ambient air for heat dissipation.

Water-cooled systems: They use water circulation to remove heat from equipment, requiring significant water usage, particularly in cooling towers for large systems. They offer efficient heat dissipation and lower temperatures compared to air-cooled systems.

Comparing both cooling systems based on:

  • Water consumption: Air-cooled systems have lower to zero water consumption, while water-cooled systems require significant water usage.
  • Operating costs: Air-cooled systems generally have lower operating costs due to reduced water usage and maintenance.
  • Environmental impact: Air-cooled systems are more environmentally friendly in terms of water conservation and avoiding water discharge.

The selection of a cooling system for data centres involves factors such as location, efficiency, cost analysis and energy consumption.

Efficient cooling systems

The data centre industry has grown significantly from a few kW to hundreds of MW, necessitating the use of efficient cooling systems such as air-side economisation, waterside economisation, evaporative cooling and free cooling chillers.

Key challenges

The key challenges of new and emerging sustainable design and construction trends include:

  • Land use: Environmental impact assessment, regulation ambiguity, authorities having jurisdiction engagement.
  • Power supply: Accessibility, connectivity and timeline issues.
  • Soil and groundwater contamination: This is a deal breaker as it affects commercial terms.
  • Fibre connectivity: Inappropriate fibre connectivity is an issue.
  • Local implementation: Prototype adaptation, MEP adjustment, talent, supply and construction issues.

Based on a presentation by Dr Sanjay Gambhir, Executive Director, AECOM India Private Limited