Abdullatif Ben Nakhi, CVol

Prof. Abdullatif Ben-NakhiDepartment of Power and Refrigeration

College of Technological Studies - Kuwait

The Prospective of District Cooling

for Residential Sector in Kuwait

Outline

Current status of DC in Kuwait

HVAC market for residential buildings in Kuwait

General benefits of DC systems

The need for DC in Residential Suburbs in Kuwait (RSK)

The feasibility of DC in RSK

The barriers against utilizing DC in RSK

Suggestions for tackling those barriers

Prof. A. Ben-Nakhi2 Kuwait District Cooling Summit - 2011

Outline









DC Projects in Kuwait

Project

Cooling

Capacity

(RT)

Sector Type

Kuwait University

(Shuwaikh Campus)

12,000 Campus Private

Kuwait Oil Company 8,400 Suburb Private

The Avenues 7,200 Shopping Mall Private

PAAET 6,000 Campus Private

Bayan Palace 5,000 Offices and

Convention Center

Private

Ministries Complex 3,600 Offices Private

Kuwait International

Airport

3,250 Airport Private

Kuwait University

(Shdadiya Campus)

112,000 Campus Private


Shuwaikh Campuses

Prof. A. Ben-NakhiKuwait District Cooling Summit - 20115

Current Status of DC in Kuwait The concept of district cooling in Kuwait is not new, as it has one of the

pioneer district cooling plants installed over 50 years ago.

Private, such as a multi-building campus, district cooling is common for new projects in Kuwait.

Because of the advantages of DC over DX option,

MEW code of practice (R-6 and R-7) encourages employing chillers by allowing higher W/m2 (e.g., for shopping mall the W/m2 = 70 for DX and 82 for air cooled chiller)

However, no district cooling system in Kuwait was installed as a public utility system.

This is because public utility district cooling system requires:

Beside the economic and environmental benefits required by private DC systems,

Community support, and

Political backup.Prof. A. Ben-Nakhi6 Kuwait District Cooling Summit - 2011

Community resistance

Political ignorance

Outline









Projected HVAC Market for Residential

Buildings in Kuwiat

Residential buildings consume about 60% of national power (DC

Consortium Report 2009).


Buildings’ air conditioning accounts for 70 % of Kuwait's peak power demand and over 50 % of the annual energy consumption (MEW, 2009).

Over 70,000 residential buildings are projected to be built in Kuwait over five cities by year 2015 (DC Consortium Report 2009).

Outline









General Benefits of District Cooling

Systems


Benefit from district cooling systems in a community can be

grouped into:

building owners,

municipality, and

society at large

Benefits to Building Owners Within the owner’s building:

No on-site HVAC refrigeration cycle.

Expected frequency of replacement of refrigerants (and subsequently

HVAC units) due to environmental commitments.

Significantly reduce cost of on-site HVAC operation and maintenance.

FCU and AHU

Induction units

Less space occupied by HVAC system (on roof swimming pool and garden).

Better for on-site utilization of sustainable or renewable energy sources.

Outside the owner’s building

Lower cooling cost

Higher operation efficiency for the refrigeration cycle

Cooler local micro-climates (no on-site condensers)

Utilization of inexpensive or waste energy sources

Greater HVAC reliability (back up and stand by)Prof. A. Ben-Nakhi11 Kuwait District Cooling Summit - 2011

Benefits to Municipality

Added infrastructure to the community (added value to

involved buildings)

Opportunities of using local energy sources

Al-Qurain city can employ gases (mainly methane) emission from

the landfill site as a source of heat for absorption DC cycle

Better management of local waste

Jaber Al-Ahmad city can utilize waste heat from Doha power

plants as a heat source for absorption DC systems


Benefits to Society at Large

Considerably higher potential to protect our environment.

reduce atmospheric emissions (energy efficiency and practice),

decrease global warming (refrigerants and practice), and

cut the release of ozone depleting gases (refrigerants and practice)

Superior energy conservation prospective.

higher components’ efficiencies

advanced design and operation approaches

Layout of piping network (optimization by AI)

Configuration of cool production plant

Adaptive control (use of NN)

Employment of thermal storage for peak power shaving and replace

part-load chiller operation

Integrated life-cycle design of DC system


Outline









The need for DC in RSK The HVAC related problem:

Extremely high electricity capacity and power are required for cooling the projected residential cities (i.e., five cities).

Significant direct and indirect environmental impacts will be associated with HVAC systems operation in the new cities.

The DC-based solution:

Literature: DC is a matured technology for reducing electricity requirements and environmental impacts of HVAC systems: Efficient refrigeration cycle much better monitored by qualified

technicians

Remote refrigeration cycle allows utilizing toxic and flammable but environment friendly refrigerants.

Proof: in other GCC countries, DC is a proven approach for: Energy conservation, and

GHG emissions reduction (e.g., CDM).


Outline









DC for Residential Areas


DC systems consist of three primary components:

Central plant

Distribution (or piping) network

Consumer systems (direct or energy transfer stations ETS).

Transmission and distribution system usually constitutes most of the capital cost for the overall DC system

Feasibility is inversely related to the size of the distribution network.

Accordingly, DC systems are most attractive in serving high-density building clusters with high thermal loads.

Low-density residential areas are usually not attractive markets for DC systems

Three of the Major Factors for

Feasibility of DC

High thermal load density: high cooling capacity is needed

to cover the capital investment for the transmission and

distribution system (up to 70% of total cost for DC system)

High annual load factor: is defined as the ratio of the average

load throughout the year on an energy system to the maximum

load on the system during that year. It is a measure of thermal

load annual profile.

High load diversity: diversity factor is the ratio of the actual

maximum demand of a facility to the sum of the maximum

demands of the individual parts of a facility


Evaluation of the Factors for Feasibility of

DC in Residential Suburbs in Kuwait (RSK)

High thermal load density: Harsh summer weather (DBT goes beyond 50 C). Residential houses in Kuwait are huge (400 m2 plot area with over 800 [up

to 1280] m2 built-up area). It is allowed to build 4 levels over a basement.

Residential suburbs in Kuwait are densely built-up (marginal green areas).

High annual load factor: Very long cooling season (about 10 months) High internal heat sources: Over lighting even with no occupancy

Circulating warm water throughout the building constructions

Number of occupants (above 8)

Style of life (e.g., cooking, use of appliances)

High diversity factor: Diversity in building types in residential suburbs in Kuwait


Assessing DC for Residential Sector

in Kuwait

A consortium was established to conduct a comprehensive feasibility study for the National Housing Authority (NHA) and MEW about the use of DC system for residential and inner city application in Kuwait.

The consortium was sponsored by Kharafi National (KN) and Kazema Engineering Projects (KEP), and it consisted of the following parties:

Dar SSH International Consultants,

Kuwait Institute for Scientific Research (KISR),

Kuwait University (KU) and

National Environmental Services Co. (NES).


Comprehensive Feasibility Study

WaterCAD software was used in configuring DC piping network.

Hevacomp software was employed to estimate the cooling load for the buildings and the overall load for the DC system.

KISR reviewed DC design, and calculations of power and energy for the conventional air-cooled and DC systems.

KISR estimated the saving in the cost of electricity for DC

KU verified thermal load profiles for the buildings and DC system.

KU calculated the amount of heat gain by the distribution network

KU analyzed piping stresses due to thermal contraction.

Wataniya Environmental Service Co. (WES) performed the environmental impact assessment (EIA).

KU evaluated the EIA report.


Study Outcome


The use of DC system for residential buildings in sectors A5

and B of Jaber Al-Ahmad City can reduce

peak power demand by 46 % (26.9 MW), and

annual electricity consumption by 44 % (80.3 GWh) compared

to the conventional air–cooled system.

power station construction cost by 12 M KD

power transmission cost by 1.5 M KD

yearly carbon emissions by 50,000 metric ton (based on crude

oil primary fuel usage)

More Studies?

While DC is proven, there are some advanced technologies that

can improve efficiency and operational benefits (e.g., integrating

DC with CHP).

Kuwait-specific research could be conducted to:

adopt the advanced technologies

prevent inefficiencies in operation (e.g., poor dehumidification)

Advanced integrated dynamic year-round simulation environment

can be used to better assess thermal performance of DC in RSK.

Energy auditing for existing DC systems.

Pilot DC project applied to a residential suburb or district.

Many more.

However,Prof. A. Ben-Nakhi23 Kuwait District Cooling Summit - 2011

Our Appeal

“Let’s take this chance!”

“Let’s start now”


Outline









The Current Status for DC in RSK


There is an urgent need for DC in residential suburbs in

Kuwait

DC feasibility is theoretically proven for residential

suburbs in Kuwait

DC effectiveness is demonstrated in GCC countries

with conditions similar to that in Kuwait

However, DC is not employed yet for residential suburbs in

Kuwait?

“What are the major obstacles ?”

Major Barriers Barriers related to non-governmental DC Investors for RSK: Starting DC for RSK is Risky Long payback period exceeding 10 years

No political support

There is no legislation for DC market (e.g., protect the investor)

Overall billing and collection of several and different types of customers

Requires access to municipal property

Resistance from unitary AC (installation and maintenance) companies

Barriers related to the government: Absence of political support There is no formal DC related strategy

There is no policy supporting DC industry

Barriers related to the community (hence, Kuwait Parliament): Fear from inefficiencies due to misuse by other linked users Lack of trust in charging and billing processes Ignorance of service quality control mechanisms Avoid monopoly in an essential service.


Outline









The Government Should Initiate the

DC Boost in RSK Initiate involvement of government bodies, especially: MEW, NHA,

and EPA

Develop national vision and strategy for encouraging DC: Voluntary GHG mitigation target Cope with refrigerants phase-out commitments

Employ DC related technology transfer via environmental treaties. UNFCCC has published an updated version of the handbook on

conducting technology needs assessment for climate change (November 2010)

Utilize CDM for DC in RSK. Tabreed is closely working with Masdar to get CDM credits for projects

including the Dubai Metro

Publish code of best practice for DC in RSK. Optimization of design and operation of DC system is a complicated task

due to the almost infinite number of decisions through the life-cycle of the system


The Government Should Initiate the

DC Boost in RSK - Concluded

Produce DC supportive policies: Incentives for DC users Reduced financing costs for DC investors Cheap rental for the DC plants room Introduction of off-peak electricity rates

Legislate the DC market: Protect participants Control cost and quality

Design and build DC piping network and infrastructure (free for the community)

Sponsor further application-oriented studies. There is an on-going research project (Annex IX 2008 - 2011) by

International Energy Agency DHC/CHP under the title “Fundamental Benefits of District Heating and Cooling to Society and a Model to Quantify and Evaluate the Benefits”


DC Services Supply Code - 2009Energy Market Authority of Singapore

The process by which the code can be modified is clarified.

The supply and return temperature ranges are specified.

Supply availability (99.5 % annually) and reliability are controlled .

The DC service shall be measured by metering equipment with

accuracy no less than 3% at the normal flow of chilled water.

The accuracy of the metering equipment shall be verified at first

installation and subsequently at intervals not exceeding 5 years by

an independent testing laboratory

The Licensee shall invoice its customers at least once a month in

accordance to its published tariffs approved by the Authority.


Thank youProf. Abdullatif Ben-Nakhi

[email protected]


Documents

Abdullatif Ben Nakhi, CVol