University of
Malta
Member of Eurobat
The potential of battery energy storage
for grid connected
domestic renewable sources of energy
University of
Malta
Renewable Energy sources – A must !
Battery storage – an interesting option !
European targets
increase in Oil prices
Reliable energy
Reliable Investment
Member of Eurobat
University of
Malta
Member of Eurobat
Above Targets are set on the gross final consumption of energy
In the case of Malta Electricity generation accounts for 66.26% of
the energy demand
Percentage energy demand of the various
sectors
University of
Malta
Member of Eurobat
Energy Generation on small islands
( 65 small islands power systems )
Islands run on HFO/LFO
In most cases the prime mover is an ICE run from diesel
The medium sized islands have a steam turbine and / or a gas turbine
Some islands have a small
percentage of hydro power
In rare cases there is a small
percentage of energy from wind
Power generation and energy produced in Cyprus and Malta
University of
Malta
Member of Eurobat
Crude oil price trend
2008 peak
10 %
$96
8%
Oil price trend line with / without 2008 peak
Oil price average during the past year
Price of oil is on the increase
Small islands are very vulnerable to oil price
fluctuations
University of
Malta
Member of Eurobat
Electricity energy demand in Malta over the past 5 years
Energy demand is mainly in the summer months
making Solar Energy an attractive renewable for Malta
University of
Malta
Member of Eurobat
Energy from a Photovoltaic Reseach plant at Abertax
It is very clear that;
Energy generation follows the energy
demand
Solar Energy can support the grid and
control the peak demand
18 KWp plant
at Abertax
KW17, Corradino Malta
University of
Malta
Peak Power demand variation over the past years
Peak power shifted from winter to summer mainly due to use of
heat pumps
Power peaked in 2007. This was reduced and controlled by;
The sharp increase of the energy tariffs
Energy efficient measures
Use of renewable sources of energy
Some of the decrease was also attributed due to the recession
Member of Eurobat
University of
Malta
Member of Eurobat
Energy Generated over the past years
Energy demand started to be controlled from 2004
Sharp decrease in 2009 is partly due to the reduction
in the industrial activity
University of
Malta
Member of Eurobat
Effect of Energy generated and from the power station
and a 65MWp PV
In Malta this means;
96 GWh/year
4.3 % of the electrical energy
2.9 % of the total energy
University of
Malta
Member of Eurobat
Effect of 65MWp PV on the electricity peak power demand
The effect of PV on the peak power
is very interesting.
A 65MWp PV plant generates
12.5% of the peak power
electricity demand
A 65MWp PV plant will shave the
peak completely reducing the
power station capital investment
PV also provide shade on our flat
concrete roof which in most
cases are not very well insulated.
University of
Malta
Member of Eurobat
Malta present electricity tariffs
Heavy consumers are already paying a
substantial price for electricity
PV feed in tariff is currently 25 euro
cents
Battery energy storage is very
attractive with this tariff structure
Battery storage has the added
advantage of allowing the PV system
to run in case of grid failure
Tariff Calculation with 25%
profit using a 48V 130Ahr
lead acid for energy storage
Present electricity tariffs in Malta
University of
Malta
Member of Eurobat
A grid connected PV system with battery energy storage
and an online battery monitoring
University of
Malta
Member of Eurobat
Possible Scenario
At the moment I have a 2.5KWp PV
system i.e enough to cover 100% my
energy needs.
And a 9kWhr battery in my electric car
However,
If the grid is lost I cannot even power my fridge
and emergency lights !
And have to pay 70 cents if I fall in band 6 !
- It is possible to set up a small battery energy
storage and with careful management and
control I can ;
run the system without the grid
Store energy and use it for my own
consumption at a profit
Make use of my 9KWhr car battery in case of
a disaster
+
University of
Malta
Member of Eurobat
A grid connected PV system which is expected to deliver
the yearly energy.
reading number
1
date
days from first reading
2
3
4
5
6
7
24/11/2011 09/01/2012 27/01/2012 18/02/2012 04/03/2012 19/03/2012 21/03/2012
8
9
10
11
31/03/2012 16/04/2012 25/04/2012 04/05/2012
Y
0
46
64
86
101
116
118
128
144
153
162
electricity meter import value
GI
6784
7362
7644
8184
8392
8592
8606
8684
8751
8801
8848
electricity meter export value
GE
1712
1941
2053
2170
2271
2380
2400
2506
2668
2774
2887
old inverter
S1
3019
3193
3272
3370
3448
3531
3546
3623
3730
3797
3869
new inverter
S2
1395
1575
1656
1756
1836
1920
1936
2014
2120
2187
2258
MRA meter reading
ST
2902
3256
3417
3616
3773
3939
3969
4124
4336
4469
4611
(n = reading number)
ref
total solar energy generated [ST(n) - ST(1) ] / [ Y ]
[A]
total exported energy [GE(n) - GE(1) ] / [ Y ]
[B]
total imported energy [GI(n) - GI(1) ] / [ Y ]
net energy consumed from grid
total energy consumed
% solar energy generated
results / day results / day results / day results / dayresults / day results / day results / day results / dayresults / day results / day
7.7
8.0
8.3
8.6
8.9
9.0
9.5
10.0
10.2
10.5
5.0
5.3
5.3
5.5
5.8
5.8
6.2
6.6
6.9
7.3
[C]
12.6
13.4
16.3
15.9
15.6
15.4
14.8
13.7
13.2
12.7
[C] - [B]
[D]
7.6
8.1
11.0
10.4
9.8
9.6
8.6
7.0
6.2
5.5
([C] - [B]) + [A]
[E]
15.3
16.2
19.3
19.0
18.8
18.7
18.2
17.0
16.5
16.0
( [A] / [E] ) x 100
[F]
50.4%
49.8%
43.1%
45.4%
47.6%
48.5%
52.5%
58.7%
62.1%
65.8%
calc between dates
results / day results / day results / dayresults / day results / day results / day results / dayresults / day results / day
total solar energy generated
11.1
15.0
15.5
13.3
14.8
15.8
total exported energy
6.2
5.3
6.7
7.3
10.0
10.6
10.1
11.8
12.6
total imported energy
15.7
24.5
13.9
13.3
7.0
7.8
4.2
5.6
5.2
net energy consumed from grid
8.9
9.4
19.2
9.0
10.5
7.1
6.1
-3.0
-2.8
-5.9
-6.2
-7.3
total energy consumed
18.4
28.3
17.6
17.1
12.0
12.7
7.3
8.6
8.4
% solar energy
generated
48.6%
32.0%
59.5%
64.6%
125.0%
122.0%
181.2%
172.7%
186.8%
easter week 4 days
to add new dates:
in gozo included
● copy column F
● paste it in a new column
replace the date in the 3rd row
●
University of
Malta
Member of Eurobat
Thank You
Contact:
Prof. Joseph Cilia
[email protected]