Electricity + Control August 2017

Electricity

Control

AUGUST 2017

Natural groundwater

reservoirs arewell suited

to storage of thermal

energy over long periods.

Use of ATES technology

significantly reduces en-

ergy consumption and

therefore CO

emissions.

An ATES plant is easy

to establish in a manner

that has no conflict with

groundwater extraction

for drinkingwater supply.

o you know that the high-tech installations

include cutting-edge heating, ventilation

and air conditioning? This is precisely the

secret to the luxurious Crowne Plaza Copenhagen

Towers Hotel having trimmed its CO

footprint and

the energy bill. Thanks to a groundbreaking heat-

ing and cooling system hidden in the basement,

electricity consumption is now 60% lower than

4 800 comparable hotels in the InterContinental

Hotel Group (IHG). Due to this and other initia-

tives this hotel runs five times as efficiently as the

IHG standard. It has won numerous international

awards, including that of the most environmentally

friendly hotel in the world.

90% energy savings thanks to smart

HVAC alone?

Yes. The ground water heating and cooling system

installed here is known as Aquifer Thermal Energy

Storage (ATES). ATES is an innovative open-loop

geothermal technology, in use at over 1 000 sites

mainly in Scandinavia and the Netherlands as an

energy-conserving measure for large buildings. It

is gaining popularity with good reason. For a start,

it can reduce the total energy consumption for

cooling and heating of a building by approximately

70%; and more than 90% for cooling alone, com-

pared to conventional technologies.

The ATES system delivers a Coefficient of Per-

formance (COP) of up to 40, which means that the

cooling power is up to 40 times

the electricity consumed by the

installation. Normally the COP

for a building of this size would

be only four or five.

The Danish expert in ATES is

Stig Niemi Sørensen, PhD, who

explains that natural groundwa-

ter reservoirs are well-suited to

storage of thermal energy over

long periods. Use of ATES tech-

nology is well-proven to enable

significant reduction in energy

consumption and therefore in CO

emissions aris-

ing from fossil-fuel-based energy production. An

ATES plant is easy to establish and has only lim-

ited thermal effect upon the natural groundwater

reservoir. It can be established in a manner that

ensures no conflict with groundwater extraction

for drinking water supply.

New territory pays off

Allan Agerholm (Chief Hospitality Officer, BC Hos-

pitality Group A/S) was on the Crowne Plaza team

that originally established the ATES system, and

sums up the results: “When you venture into new

territory, as we did, putting in the first groundwa-

ter based heating and cooling system in Denmark,

you’re always a little bit worried; will your partners

deliver? And I have to say that working with Dan-

foss on this project has been a tremendous suc-

cess.

“We’ve had very few challenges. In fact, the

system has delivered precisely what it was calcu-

lated in theory to do; that is to deliver in the re-

gion of 90% energy savings during the summer

months, and in the region of 60% during the win-

ter, which is really outstanding.”

So how does it work?

The Crowne Plaza ATES used a suitable natural

ground water reservoir, known as an aquifer, into

which two thermal wells were installed, for stor-

Ground Water

Cooling System

Jesper Thurbo, Danfoss

I guess it comes as no surprise to hear that the essentials of running a luxury hotel

are something to do with exquisite catering, gorgeous interior design, and innova-

tive technology.

TEMPERATURE MEASUREMENT

Take Note!

abbreviations

The system

has delivered

precisely what it

was calculated

in theory to do

– 90% energy

savings in

summer, and

60% in winter

ATES

– Aquifer Thermal

Energy Storage

COP

– Coefficient of

Performance

HVAC

–Heat, Ventilation, Air

Conditioning

IHG

– InterContinental

Hotel Group

VSD

– Variable Speed Drive