PresentationPDF Available

Control of Electric Hot Water Heating Systems for improvement of PV self-consumption

Presentation

Control of Electric Hot Water Heating Systems for improvement of PV self-consumption

Abstract

Presenting the results obtained from the analysis of 630 households from Solar Analytics data-base with rooftop solar and electric hot water heating system (inc. heat pump)
Control of residential electric water
heating systems (EHWS) to
improve PV self-consumption
Baran Yildiz
Research Associate
School of Photovoltaic and Renewable Energy Engineering, UNSW, Sydney, Australia
Solar Analytics
Energy required per shower
1,2
0.3 ~ 0.6 kWh per minute of hot
shower






!"#
$%

!&"#
''( (
)*+,-./"001 .
)*+'',203  2,4$
Australian Statistics on hot water energy
On average around 1/3rd of total residential
energy use is used to heat water 3
More than half of the total energy for
heating water comes from electricity hot
water storage system (EHWS) 4
*4,5'(
67,5'(
),'(
89",'(
5
: .$13)0*+0"9;<=4$
)1)0''&
20,:0 ::>: .:?.'
NSW QLD SA
 '
'
 '
'
Continuous Controlled
Control of continuous EHWS
Why?
An average size hot water storage tanks can store around 10 kWh of thermal energy
Improve self-consumption rate of rooftop PV systems:
<$0.0@011
0 %
A0310
200.00$$0 28@
Reduce network demand: previous Ausgrid research showed that each continuous electric hot
water system contributes to the peak demand 0.25kW and 0.5kW per customer in summer and
winter respectively.5
B
)  000) '5
Control of continuous EHWS
&
D
C
Gri
d
Invert
er
Hot water
tank
Control
of HW
circuit
Primary control by tank
thermostat
Resistive heating element
Import tari*: household & hot
water tank
Solar feed in tari*
Demand response signals
Time of day & available excess
PV generation
Hot water tank status
Simple timers, intelligent timers
and diverters
EHWS Control tools
EHWS Control tools
'
Analysis of Solar Analytics Database
630 households from Solar Analytics data-base with EHWS
-0
28 
:4-
~ 1 calendar year (2018 Oct- 2019 Oct) in 5 minutely resolution
What is the best control method for a household with EHWS?
010 ,000 
$CDE0%
01E128F
A03F

PV utilization on EHWS

PV used for EHWS /Total
EHWS (%)
On average:
Default: 17%
Simple timer:
46%
Intelligent timer:
58%
Diverter: 70%
O*-peak: 0%
PV self consumption

PV used for EHWS /Total
PV(%)
On average:
Default: 8%
Simple timer: 18
%
Intelligent timer:
22 %
Diverter: 30 %
O*-peak: 0%
Savings for NSW households

,% ..% 
$%
On average:
Simple timer:
$94
Intelligent timer:
$125
Diverter: $200
O*-peak: $250
Payback time for NSW households

On average:
Simple timer:
3.5 yrs
Intelligent timer:
3 yrs
Diverter: 5.5 yrs
O*-peak: 1.5 yrs
Savings for QLD households
5
,% ..% 
$%
On average:
Simple timer: $
84
Intelligent timer:
$ 110
Diverter: $184
O*-peak: $ 110
Payback time for QLD households
B
On average:
Simple timer:
3.5 yrs
Intelligent timer:
3 yrs
Diverter: 5.2 yrs
O*-peak: 2 yrs
Savings for SA households (majority off-peak
households)
&
,% ..% $%
Conclusions
Financial implications
<DED00.$1*4)0
"0000.$30167=*40!G.2HI#3
1)!@$3 .3#
431@FJK$012801.

Network’s point of view
2028@00L0
): @!*I"B''# 0D J0
 *I"B''J$01:-401
Technical point of view
7$130.3.3
7$.>0.5
70. 0.$:-4030%%0
$%00 ,J";"E2-:MN0
)0.
!%%0#

0$>0.7%M
O00
Thank you!
For more details:
https://www.researchgate.net/project/CRC-P-Integrated-Smart-Home-Energy-
Management-Technologies
'



ResearchGate has not been able to resolve any citations for this publication.
ResearchGate has not been able to resolve any references for this publication.