IN-DUCT EVAPORATIVE COOLING
Decarbonisation is being driven by legal regulation and financial risk. Upgrading heating, cooling and humidification systems will soon not be optional for any landlord, as failing to meet the Minimum Energy Efficiency Standards will mean a building cannot be legally leased. Given the number of properties needing to make improvements, as the deadline approaches it’s likely that competition for labour and building products will increase.
doesn’t help our carbon reduction goal, as the overall energy and carbon emissions in this circumstance will be identical to the gas-fired humidifier we’re looking to replace. However, often decarbonisation initiatives involve replacing gas boilers with heat pump chillers, alongside exchanging other gas-fired systems. If this is the case, and the heating prior to the adiabatic humidifier can be achieved with a heat pump, the overall electrical load will be much less than using self-generating electric steam humidifiers due to the heat pump’s COP. As the adiabatic humidifier itself uses a very small amount of energy to simply circulate water, employing it in combination with a heat pump chiller, could result in the energy consumption being three times lower then self-generating electric steam humidifiers for the same humidity output.
Adiabatic humidifiers, such as the Condair ME, also offer excellent opportunities to
reduce a building’s cooling energy consumption with associated carbon reductions. An evaporative humidifier will deliver 0.68kW of cooling for every 1kg of water evaporated. As a single unit will operate on less than 1kW of electricity whilst evaporating up to 1,000kg/h of water, the potential for low energy, high-capacity cooling is significant if it can be effectively employed. Using direct air evaporative cooling (DEC) strategies to cool commercial buildings, rather than mechanical cooling, has a very limited potential. Buildings need to maintain mid-range indoor humidity levels, which a DEC strategy would struggle to do, and it relies on favourable outside air conditions for the water to evaporate. However, modern indirect AHU strategies, such as Exhaust Air Evaporative Cooling (EAEC), avoid both these limitations and offer consistent cooling performance.
Rather than humidify and cool the incoming airstream, an EAEC system cools the extract
air from a room with an evaporative humidifier. The return air has a relatively stable condition and can be humidified close to saturation to achieve the highest possible cooling effect. This cool wet return air is then fed through a heat exchanger before being vented externally. The heat exchanger transfers the cool thermal energy to the incoming airstream, cooling it by up to 10K.
As the humidity increase is only on the return air, there is no impact on indoor humidity levels. The efficiency of an EAEC system does rely on the heat exchanger, but even with a modest 70% HX efficiency, a typical building in London could reduce its reliance on mechanical cooling by around 40% with this strategy. Whilst it’s not a universal solution, EAEC offers real and achievable benefits for energy reduction and decarbonisation initiatives. Decarbonisation is being driven by legal regulation and financial risk. Upgrading heating, cooling and humidification systems will soon not be optional for any landlord, as failing to meet the Minimum Energy Efficiency Standards will mean a building cannot be legally leased. Given the number of properties needing to make improvements, as the deadline approaches it’s likely that competition for labour and building products will increase. Early planning could avoid regulatory penalties and lost rental revenue. Condair offers
free, expert advice for any building operator or facilities manager looking to explore their humidification or evaporative cooling options to help meet or exceed the EPC B-rating prior to the deadline.
Read the latest at:
www.bsee.co.uk Contact us for free expert advice
Tel: +44 (0)1903 850 200 Email:
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condair.com Web:
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Humidification, Dehumidification and Evaporative Cooling
Condair hpv BSEE
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When used in an AHU, the Condair ME delivers up to 800kW of cooling from less than 1kW of electricity.
Put Condair technology at the heart of your evaporative cooling strategy.
Condair ME Evaporative cooler
Evaporative cooler
Outside air Return air
Supply air
Exhaust air
CIBSE-approved CPD’s available
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