New York’s Empire State Building may be more than 90 years old but it’s breaking new frontiers in energy efficiency. One advance is the use of a Hydromx in its many heating systems, with savings of around 20% being achieved.
When Tim Dailey took on the role of director of engineering for New York’s iconic Empire State Building in 2015, one of his first moves was to swap the water in its heating systems for a nanofluid. Dailey had been one of the first people to trial the fluid, Hydromx, when he worked for the New York Stock Exchange, so he knew the benefits first hand.
Hydromx is a glycol-based solution containing extremely small particles which enhance its thermal properties. It heats up or cools down more quickly than water and reaches a steady state sooner too. A mix of 50% Hydromx and 50% water reduces the energy used for a heating or cooling system by between 20% and 40%, with a similar reduction in carbon emissions.
“Because of the savings on the heat transfer, energy use is greatly reduced,” Dailey explained. “I would take a stab for the payback to be around three years – although that’s something we are going to have measured by a third party.”
Constructed in 1930 and 1931, and then the world’s first building over 100 storeys, the Empire State Building (owned by the Empire State Realty Trust) today aims to set a high bar for energy efficiency. It first received a LEED Gold rating from the US Green Building Council in 2011 and was most recently reclassified as Gold in January 2020.
Early adopter
Dailey first used Hydromx in an air conditioning system back in 2012 while working for the New York Stock Exchange, having come across the nanofluid at an industry seminar. “We filled up a riser at the top of the building and it was very, very successful,” he said.
One of the main attractions for Dailey at NYSE’s 11 Wall Street was Hydromx’s low freezing point, -26 degrees C. “We get very cold here in New York City and have problems with freeze ups so we would have to drain the whole section of the building and load layup chemicals to protect the building,” he explained. “This is very expensive and very time consuming and means that the system sits all winter without the ability to use the air conditioning.”
At the Empire State Building, Hydromx has been installed incrementally in the building’s many heating systems as construction projects have been undertaken. “There is always a great deal of construction underway,” said Dailey. “This is a 3 million square foot building with 120 tenants.”
The 443m-high building – if you include its spire and antenna – has several uses. It is home to the Observatories which receive more than four million visitors a year, a broadcasting team for radio and television, offices and retail on the ground floor. As well as lowering the Empire State Building’s carbon footprint, the use of Hydromx improves the economic situation for its tenants, as Dailey explained: “Everybody is happy because the utility bills are lower. The savings are around 20% compared to water due to the nanoparticles.”
Now all the building’s heating systems contain Hydromx, the latest installation being part of a $200m refurbishment of its Observatories. The nanofluid also went into a heat recovery system, which wins back heat lost as the air within the visitor spaces is refreshed.
Dailey explained: “We worry about carbon dioxide when there are so many people in a space, so we have huge 35,000 CFM (cubic feet per minute) DOAS (direct outside air system) fans, two of these in one of the spaces. That drives the heating and cooling a little bit wild, which means more cost, so grabbing back some of the heat where the air is extracted saves a lot of energy and makes up for some of the waste.”
Installation of Hydromx is straightforward, said Dailey. The system is drained down, flushed twice with water which is tested to make sure the system is clean and then a 50:50 mix of Hydromx and water goes in. “It’s a Friday night to Sunday morning job,” said Dailey. “We did it in the shoulder season, which is Spring or Fall.”
“We used to run both full out on a hot day but now we never need to run the second chiller,” reported Dailey. “The chillers are much more efficient machines and the electrical use of the central plant is basically half what it was. Pumping is down, chillers are down and chiller reaches its sub point faster.”
The Empire State Realty Trust has also installed Hydromx into cooling circuits – although not in the Empire State Building itself yet. Two years ago, as part of an extensive upgrade, the Trust installed in an 11,000-gallon primary chill-out loop at 1350 Broadway, a 25-storey office building, which has two 350-ton electric chillers.
Dailey would consider using Hydromx in the cooling systems for the Empire State Building itself but that would require a major programme of works. “You are talking 60,000 to 70,000 gallons of chilled water and five miles of pipe,” he said. “We would have to make sure that the pipe work is in the right state and that we were doing it at the right time. And bear in mind that the steam chillers are 83 years old and the electric machines are around 30 years old.”
Anyone considering using Hydromx as part of an upgrade or refurbishment would be well advised to ensure they had no leaks first, said Dailey. His strategy is to have 10% of the volume of installed Hydromx fluid in storage in case there are leaks. At the Broadway building, retractable storage vessels are on hand to hold the Hydromx should any drain down for maintenance be required.
Should leaks occur, Hydromx gets a bit tick for being non-hazardous: “There are alternate products out there but they are highly toxic, so any sort of a leak would be bad news and bad PR,” said Dailey.
Aside from the cost of replacing leaked fluid, another potential risk Dailey investigated initially was how the nanofluid reacted with the materials in the heating and cooling systems: “We did metallurgical testing after a few years and checked whether there was any damage, but it’s quite the opposite: there are no issues at all,” he said. “The strain on the pump is lighter than glycol because it’s a mixture of glycol and water. That means it’s lighter to push, uses less energy in the pump and so there’s less wear and tear on equipment.”
Dailey’s willingness to innovate is having wider repercussions in New York City. The Hydromx installations at both the Empire State Building and 1350 Broadway have attracted interest from the wider industry, with one big corporate considering deploying the wonder fluid in a next generation ‘green’ office project. And Hydromx has been accepted as a supplier by the NYC Accelerator programme which aims to speed the decarbonisation of the city’s building stock.
Read more here about how Hydromx is assisting New York City with its aim to be carbon neutral by 2050.
If you’d like to discuss installing Hydromx into your building get in touch
About Hydromx
Hydromx utilises nano-particles to speed up heat transfer from boilers into radiator systems, reducing the amount of energy required for rooms to reach the required temperature. Because boiler cycling and HVAC plant run-time is reduced, equipment lifespan is increased and maintenance requirements lessened, all adding to costs savings. Furthermore, we’ve had instances where installing Hydromx delivered the potential to increase heating/cooling capacity of existing plant sufficiently to avoid capital investment in new plant to cope with increased demand.
Hydromx is suitable for most commercial and domestic hydronic HVAC systems using water as a primary heat transfer fluid. It is a non-invasive, easy-to-install energy and carbon saving solution which works by improving heat transfer. It provides complete system protection against corrosion, calcification and bacteria and includes anti-freeze. Hydromx is inert, recyclable and guaranteed for 20 years. Depending upon the application and system characteristics, it will normally deliver energy, carbon and cost savings of between 20-35%.
Installation involves draining the system, flushing and re-filling with 50% water and 50% Hydromx. No major plant or system changes are required. The technology is backed by sound scientific principles and evidence supported by worldwide installations that have, in some cases, returned almost 50% energy savings.
If you’d like to discuss installing Hydromx into your building get in touch