Energy efficiency: Danfoss delivers on promise of system-wide gains

Friday, 20 October, 2017

Danfoss has handed air conditioning OEMs a timely boost in their efforts to meet new seasonal efficiency targets – after new simulation tools and testing facilities confirmed the promise that a drop-in Scroll with IDVs compressor could yield a 7.3% system-wide gain.

Air conditioning companies worldwide are responding to challenging targets for energy efficiency. This is especially true in Europe, where Eurovent data showed in 2015 80% of today's air conditioning chillers would fail to meet Minimum Energy Performance Standards (MEPS).
In most major markets, new standards are being introduced based on weighted part-load figures to give a more accurate reflection of year-round power consumption.

Danfoss has launched a raft of measures to help its OEM customers respond:

New compressor technology – giving an immediate, system-wide seasonal efficiency boost from 6 to 12%
System seasonal / part-load efficiency simulation – to predict the efficiency impact of components and designs
Psychrometric testing rooms – allowing OEMs to validate their updated product ranges
Matthieu Stoll, Danfoss Global Marketing Manager for Air Conditioning Compressors, said: "A/C manufacturers have a lot of work to do, and quickly. At Danfoss, we're ideally placed to help." 

"We have the most complete portfolio of components, which gives us in-depth knowledge about how they behave and about their value in the system. That means we can give OEMs immediate assistance at a system level, and long-term support."

Launched in late 2016, IDV technology dramatically improves scroll compressor efficiency when the system is under partial load. This is especially important for seasonal and part-load efficiency measures like Seasonal Energy Efficiency Ratio (SEER) and Integrated Part Load Value (IPLV) that are heavily weighted to prioritize part-load efficiency.

The new technology is being rolled out now. And because the new compressors are backward-compatible with existing Danfoss products, they can be exchanged like-for-like, with minimal redesign costs.

Measured in a psychrometric room, making this one switch improved a rooftop unit’s overall SEER score by 7.3% – enough to pass the challenging Tier 2 Ecodesign target.

The tests also validated a new simulation model, which allows manufacturers to compare the system-wide effects of component and guide their design choices. At every load point, the simulator predicted the real results to within 1%.

Matthieu Stoll says: "A designer might wonder about the SEER impact of increasing the size of the condensing coil by 2K or how a system might perform in another region. For example, this same RTU design scaled to 60HZ would yield 14.02 IEER, above the DOE 2023 target. We can now help OEMs to predict on the impact of the system performance with less physical testing of expensive prototypes."

Comparison of the measured and simulated Energy Efficiency Ratios (EER)
Source: Danfoss Simulation Tool and Danfoss Test Laboratory

All the tests took place in a double psychrometric room at the Danfoss CC factory in China. It is one of a growing number of Danfoss test facilities around the world, which the company is making available to select partner OEMs. Three new test rooms at the Danfoss Application Development Centre in Florida expands this capability still further – testing chillers to 150T, and rooftop units to 50T.

Matthieu Stoll concludes: "As an industry, we're all challenged to minimize our environmental impact. We want to talk to manufacturers, and find out what they need – so we can all succeed, together."

Tested SEER : Tested SEER with drop-in Scrolls with IDVs help meet regulations at minimal redesign cost
Tested SEER : Tested SEER with drop-in Scrolls with IDVs help meet regulations at minimal redesign cost