ALFA LAVAL Drycooler: 565 kW of Reliable Cooling for a Lithuanian Crypto-Mining Farm

UAB Šviesos energija is a Lithuanian engineering company from Kretinga. Since 2016, the company has been developing the local power generation business, focusing on solar plants, gas piston cogenerators and heat recovery systems. The average annual output is about 1.2 GWh, of which approximately 40 per cent is consumed by the company’s own facilities and the rest is supplied to the local grid.

In recent years, the company has evolved from a typical regional energy supplier into a technology platform where energy and computing coexist in a single infrastructure. On the site, it operates a hybrid plant that combines photovoltaics and a cogeneration module. And the energy generated is partially channelled to a high-performance computing cluster – a miniature computing factory where every kilowatt of electricity is turned into a digitised stream of hashes that support the uninterrupted operation of the mining cluster and the financial stability of the company’s entire energy ecosystem.

The cryptomining project was a natural extension of Šviesos energija’s engineering philosophy – to utilise surplus energy where it can bring real added value.

More than 220 server racks are installed on the site, each with a heat dissipation of about 650-800 W, which forms a total load of about 150-170 kW. At the same time, the heat flux density exceeds 1200 W/m², and the critical range of chip operating temperatures is 21-23°C with humidity not exceeding 55%. Under such conditions, even short-term fluctuations of 2-3 degrees Celsius lead to a 5-7% drop in hash rate efficiency and an increase in power consumption of cooling systems by up to 12%. That’s why the key task was to create a stable thermal profile – how to cool the computational heart of the company so that each mega hash remains not only profitable, but also thermodynamically and environmentally justified.

Hybrid HVAC site in the synergy of generation and cooling

The system was designed in the logic of direct heat removal by the fan circuit, where the main load is not removed by the compressor cycle, but by intensive air exchange through the glycol heat exchange front. When the outside air temperature is below 15°C, the system switches to the free cooling mode, eliminating the operation of compressors and maintaining the set temperature solely due to the heat capacity and circulation of glycol at a speed of about 0.9-1.1 m/s and an average flow rate of 98-100 m³/h. This hydrodynamics ensures a stable temperature distribution over the sections and uniform blowing of the entire fin surface. This results in a heat exchange efficiency of up to 93% of the design capacity and ensures that the temperature is maintained between 35-40°C at peak loads.

This architecture allows partial free cooling for up to 280 days a year when the outside temperature remains below 15°C. This solution has reduced the total energy costs. This solution reduced total cooling energy costs by approximately 35-40 per cent while maintaining thermal balance throughout the loop. The system uses a three-stage fan control logic: the speed is regulated by the temperature of the return glycol, which ensures that the thermal gradient is maintained and that there are no sudden pressure spikes in the lines of high-tech equipment.

The hydraulic scheme is designed with balancing isolation on two manifolds and the possibility to connect additional modules without interfering with the main line. All lines are designed for flow rates up to 100 m³/h, with working diameters DN80-DN100 and permissible pressure losses not exceeding 60 kPa. The system is equipped with service bypasses and points for thermometry and manometry, which allows calibration without stopping the process. The circuit features automatic ΔT flow correction, ensuring temperature stability of ±0.5°C and compatibility with the chiller chiller cascade.

A solution proven by time and the precision of HVAC engineers

To realise the task, the ALFA LAVAL DCDS805BD222 P, manufactured in 2005, with a nameplate thermal capacity of 565 kW, was installed. Despite its age, the unit demonstrates the condition and efficiency of the modern equipment level – thanks to the original design of fins and competent maintenance of heat-exchange sections of the selected drycooler.

The drycooler fulfils the function of the primary stage of heat removal – subcooling of the liquid before entering the process heat exchanger. The coolant circuit is water with glycol, designed for stable operation under various modes of nominal load.

The system is designed and supplied by EVROPROM with factory testing of the fan group, sections and distribution header prior to shipment. The configuration allows for integration in a cascade scheme with chillers or auxiliary drycoolers, ensuring modularity, high life expectancy and operational flexibility without interfering with the basic hydraulics.

Balance in ALFA LAVALdrycooler process parameters

The supplied equipment demonstrates a balanced combination of power, energy efficiency and compactness in this design. A cooling capacity of 565 kW with a temperature profile of 40/35 °C and an air temperature of 25 °C ensures optimum thermal balance under intensive IT loads. The base fluid used is a mixture of water and glycol, designed for stable operation at temperature variations as low as -15 °C in the cold winters of Lithuania.

The volume flow rate of the coolant is 98.4 m³/h, taking into account that the air flow is 200 800 m³/h, which guarantees even distribution of cooling in all sections. There are 10 800 mm diameter fans, which create a steady pressure with low noise level. The external heat exchange surface is 1,885 m² and the internal volume of the sections is 163 dm³. The unit dimensions are 9.7 × 1.3 × 2.5 m, mass – 1,491 kg.

These specifications formed the basis for engineering calculations of the hydraulic system of the site, including balancing of circuits, adjustment of pressure drops and flow distribution over the sections. All parameters were verified for all parameters by EVROPROM specialists at the design stage, which ensured that the actual operating conditions precisely matched the design data.

Thermal HVAC cascade architecture and system operation principles

The cooling engineering scheme at UAB Šviesos energija is based on the principle of a closed cascade, where each circuit fulfils a clearly defined function in the heat removal chain. The hot glycol circuit receives the heat load from the mining racks and directs it to the plate heat exchanger, where the primary flow separation and temperature equalisation takes place. After that – ethylene glycol with water enters the ALFA LAVAL drycooler, which performs the function of subcooling to the calculated parameters, and returns back to the system, forming a continuous thermal cycle of the set temperature.

At the growth of computing activity and, accordingly, thermal power, the system automatically connects the compressor cooling stage, which is provided by the project as a reserve.

The architecture creates a hybrid structure combining the advantages of dry cooling and classic compressor cooling, which not only ensures energy efficiency but also increases operational reliability: in case of failure of one stage, the second stage is able to compensate for the drop in performance in a timely manner. This approach makes the system resistant to seasonal and peak loads, which is especially important for such mining sites with irregular heat generation.

Advantages of choosing ALFA LAVAL with a guarantee from EVROPROM

Mining farms create pulsating peaks with heat flux variations of up to ±15 kW per second per rack. The large heat exchange area of 1,885 m² and high air exchange rates – 200 800 m³/h – allow to keep temperature variations ΔT within 0.4-0.6°C, which is critical for a stable hashrate and to prevent efficiency drops of 5-7% during short load peaks.

Cooling economics relies on fan heat removal, which reduces compressor finishing load by 25-30% and allows partial free cooling to be used up to 280 days per year, saving over 40 MWh of electricity annually. The modular architecture of the system supports the connection of additional air and glycol sections without changing the hydraulics, providing a flow rate of up to 100 m³/h per DN80-DN100 line and a pressure loss of no more than 60 kPa, while maintaining a stable thermal regime and being ready for farm expansion.

Reducing cooling costs to€75,000-85,000 per year: how EVROPROM made a mining farm economical

Taking into account the capacity of the dry-cooling cooling unit at 565 kW, the possibility of partial free-cooling up to 280 days a year and continuous operation 24 hours a day, a primary energy cost reduction of 35-40 % results in savings of around 1,575,000-1,800,000 kWh. At a tariff of 0.18 €/kW per hour, this is equivalent to 283,500-324,000 € just by reducing the operation of the compressor equipment. If you break this down by month, you get between 23,600€ and 27,000€ of savings per month. At the same time, the system retains flexibility for expansion: adding additional air or glycol sections increases cooling capacity, potentially increasing savings by another 5-10% as the heat load of the company’s mining cluster grows.

The real economic benefit, taking into account actual peak load limitations, heat transfer inertia and airflow distribution efficiency, is around 75-85,000 € per year. This includes reduced operating hours of compressor modules, lower maintenance costs, no mains water consumption and reduced risks of corrosion and bio-pollution. In terms of each kilowatt of installed capacity of the drycooler, the actual annual savings reach approximately 133-150 € per kW, which makes this implementation technically reliable and financially attractive.

Why choose EVROPROM?

EVROPROM was the single contractor for the completion, delivery and commissioning of a 565 kW ALFA LAVAL DCDS805BD222 P drycooler for UAB Šviesos energija. 10 fans with a diameter of 800 mm provide a uniform air flow of 200 800 m³/h in 10 sections with minimal local turbulence and vibrations <0.5 mm/s, and acoustics varying in the range of 50-65 dB. Factory checking of the fan group, sealing of sections, balancing and labelling of assemblies in stock minimises installation risks. Collector pipework and a 98.4 m³/h flow rate setting with ΔT allowed the temperature profile to stabilise between 21-23°C at ≤55% humidity and a total load of up to 170 kW, while automatic switching to the compressor finalisation stage is activated when the ΔT deviation is not scaled by more than ±0.5°C.

The use of a dry cooler as the first stage reduces compressor equipment operation by 25-30%, reduces operating costs, completely eliminates mains water consumption and reduces corrosion risks. The design of the drycooler with increased fin area and optimised airflow angle of attack smoothes temperature peaks, while the modular architecture allows the system to be scaled up without reassembly of the hydraulics: the lines are designed for flow rates up to 100 m³/h, pressure loss ≤60 kPa and ΔT stability of ±0.5°C. Free-cooling is efficient up to 280 days a year, reducing annual energy costs by 35-40%.

Preparation at the warehouse included section leak testing, fan balancing and labelling of assemblies. At this site, access dimensions and openings were coordinated, unloading and installation by phase, connection to the collector, monitoring of temperature and flow rate, setting of fan frequency drives and emergency protection system. All measurements are recorded by a distributed sensor network and the protocols are available to the customer. EVROPROM’s warranty periods include 6-36 months of ongoing support and advice, leak testing, inspection by HVAC engineers, preparation for shipment, certificates and customs support.

This approach turns delivery into a complete engineering solution: reducing the amplitude of temperature peaks, temperature stability, minimising compressor finishing hours and flexibility for future expansions. The project demonstrates that EVROPROM is a contractor for companies with their own generation and high requirements for reliability and economics of industrial operation.

Author of the article:
Svyatoslav Ovcharenko, Sales Manager
10.10.2025