Customer Orientated Hot Water Load Management

CUSTOMER-ORIENTATED HOT WATER

LOAD MANAGEMENT

by

Andries Stephan Wilken

Submitted in partial fulfilment of the requirements for the degree

Masters of Engineering (Electrical)

in the

Faculty of Engineering

UNIVERSITY OF PRETORIA

September 2001

"FOR THE LORD GIVES WISDOM,

AND FROM HIS MOUTH COMES

KNOWLEDGE AND

UNDERSTANDING."

- Proverbs 2:6 -

Author: A.S. Wilken

Study Leader: Prof. G.J. Delport

The reader will be introduced to the South African electrification crisis and the

benchmarks set by Eskom to contain this problem. Various load management options will

be discussed but the work done throughout this dissertation is to direct the attention

towards the possibility of implementing a customer orientated hot water load control

system. Various authors have studied ways to solve the problems found in the South

African hot water load control scenario, but their "optimum" control strategy hardly

included the needs of the end user.

Research areas include:

q Hot water load control seen from a national perspective,

q A customer-orientated hot water load management methodology designed to satisfy the

mutual needs of the utility, municipality and residential consumer,

q Hot water load control system dynamics,

q Average cylinder temperature prediction and

q Savings calculation and distribution.

It is inevitable that some emotions would be stirred when the paradigms starts to shift

towards consumer-orientated control, but something has to be done to change the current

situation.

Keywords: Hot water load control, cold-load pickup, hot water cylinder temperature,

effects of human behaviour, savings distribution.

ABSTRACT

Outeur: A.S. Wilken

Studie Leier: Prof. G.J. Delport

Die leser sal bekend gestel word aan die Suid-Afrikaanse-elektrifiserings-krisis en die

doelstellings wat deur Eskom daar gestel is om die probleem te oorbrug. Die bespreking

word ingelei deur 'n verskeidenheid lasbeheer opsies te bespreek wat dan uitloop in die

implimentering van 'n kliлnt-gebaseerde-warm-water-lasbeheer-metodiek. Verskeie

studies is oor die jare geloots om die Suid-Afrikaanse warm-water-lasbeheer situasie op te

los, maar geen optimale oplossing het die behoeftes van die residensiлle kliлnt ook in ag

geneem nie.

Navorsing sluit onder andere die volgende areas in:

q Nasionale perspektief oor warm-water-lasbeheer,

q Kliлnt-gebaseerde-warm-water-lasbeheer-metodiek wat ontwerp is om die behoeftes

van die elektrisiteitsvoorsiener, munisipaliteit en residensiлle kliлnt gemeenskaplik te

bevredig,

q Dinamika agter warm-water-lasbeheer,

q Gemidelde warm-water-silinder-temperatuur en

q Die bepaling van besparings asook die verspreiding daarvan.

Die feit dat sommige partye geafronteer gaan voel as gevolg van nuwe warm-waterlasbeheer-

paradigmas wat daargestel gaan word, is onontbeurbaar. Die residentiлle kliлnt

het vir jare lank aan die korste ent getrek en dit is nou tyd dat iets aan die situasie gedoen

moet word.

Sleutelwoorde: Warm-water-lasbeheer, warm-water-silinder-temperatuur, menslike

gedrag, besparings verspreiding.

OPSOMMING

ENERGY MANAGEMENT IN SOUTH AFRICA.......................................................... 1

1.1 LOAD MANAGEMENT .................................................................................................. 2

1.1.1 Supply-Side Management ............................................................................. 2

1.1.2 Demand-Side Management ........................................................................... 2

1.2 DEMAND-SIDE MANAGEMENT IN SOUTH AFRICA ...................................................... 4

1.3 RESIDENTIAL DEMAND-SIDE MANAGEMENT ............................................................. 5

1.3.1 Lights ............................................................................................................. 6

1.3.2 Cold Storage .................................................................................................. 6

1.3.3 Space Heating................................................................................................ 7

1.3.4 Water Heating................................................................................................ 7

1.3.5 Water Heating As The Primary RDSM Option............................................. 8

1.4