Sea Water Air Conditioning

Using deep sea water for ecological and affordable cooling solutions

Deprofundis

A new solution for middle sized structures

Baptiste BassotPresentation to Green Mondays27/10/2008

Cold generation 101

Necessary for Modern SocietyProcessesConfort

How do we produce cold?Force the opposite of a natural phenomenon

High costsEnergy intensiveGas

A sucessful approach: SWAC systems

In Toronto, Lake Ontario waters cooling 51 high-rise buildings, using 10% of conventional systems energy

Curaçao, Netherlands Antilles, Evelop Crp:90% electricity and CO2 emissions saved

Still in infancy, yet showing potential: OTEC systems

Ocean Thermal Energy Conversion

The opposite of a conventional a/c system!

Like all geothermal energy sources

Back to SWAC: Energy gains

Cooling power

0

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0 20 40 60 80 100 120 140 160 180 200Water flow (m³/s)

Co

olin

g P

ow

er

(kW

ce)

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Te

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erat

ure

(°C

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Energy savedWater arrival temperature

The cavitation problem

Cavitation in water phase diagram Cavitation damages on a pump

T°

P

Cavitation

Boil

Ice

Liquid water

Steam

Cavitation and suction limit speed

Maximum speed in suction

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Pipe outside diameter (m)

Ma

xim

um

cir

cu

lati

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sp

ee

d

(m/s

)

Max speed in suction

Energy balance

Energy balance

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0 20 40 60 80 100 120 140 160 180 200Water flow (m³/h)

Po

wer

(kW

)

Total pumping energyEnergy savedBalance

P1 : Maximum succion point

P2 : Energy optimal point

Our solution

Classical SWAC system Deprofundis closed loop

Final energy balance

Energy balance : classical system and closed loop

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0 20 40 60 80 100 120 140 160 180 200Water flow (m³/h)

Po

wer

(kW

)

Balance (open loop)Balance (closed loop)

P1 : Maximum succion point

P2 : Energy optimal point

P3 : Closed loop optimal point

Immersed heat exchanger

Geometry Massively parallel

Size 6 modules 3m x 3m x3m (400 Kg) each

Environmental topics

• Radius of 5 km of a depth of – 600m (in tropical waters)

• Material used (PEHD used for pipes, titanium for heat exchanger): no exchange with the environment for decades. Able to be re-used indefinitely + recycled

Advantages

Thin pipes Available in rolls Easy to handle Easy to deploy

Suitable for remote locations

Closed loop Control on the

circulating water No end-pipe filter No risk of aspirating

sea material Easy maintenance

A special offer

• location (distance and relief) options (PV / wind solutions for the pump) electricity costs subventions

ROI 5 years in average, for a solution least 20 years.

Parameters of a characteristic site for the study:

Intake depth : 800m (5°C) - output water 14°C

Pipe of 2150 m in PEHD : diameter 150-123mm

Open Topics for Q&A:

• Tap into different energy sources• Cold generation• Sea Water energy systems• Energy ventures

• Interesting?• Interested?• Sleepy/Hungry?

Thank you for your attention