IEEE Power & Energy Magazine - September/October 2017 - 88

Without BESS

PDiesel(MW)

f (Hz)

60
40
20
0
0

0.5
0

Without BESS

t (s)
(a)
PDiesel(MW)

f (Hz)

With BESS

t (s)
(b)

With BESS
0.6
0.5

6
t (s)

(b)

figure 6. The simulated frequency response of the system
subject to the outage of wind turbines at KLFN: (a) without
BESSs and (b) with BESSs.

figure 7. The simulated diesel-engine power output subjected to the outage of wind turbines at KLFN: (a) without
BESSs and (b) with BESSs.

Battery Energy Storage Systems

strate the performance of the system, with and without the
BESS, when the wind turbine output power changes/drops
from 300 kW to 0 very quickly due to a wind gust exceeding
the maximum acceptable turbine operating speed, thus tripping the wind generator. In this scenario, the BESS installation significantly improves the system frequency response,
avoiding frequency stability problems.
In the previously discussed test scenario, the rated output
power of the BESS is 300 kW; however, deploying such a
system may not be economically feasible for the community.
Hence, battery sizing studies should be carried out to optimize the investment and O&M costs and, at the same time,
guarantee adequate system performance and maximum fuel
cost savings. Economic analyses show that installation of
a 27-kWh BESS will reduce O&M cost by CAN$330,000/
year, as shown in Table 1. Note that adding BESSs along
with RESs will reduce the fuel cost and emissions by 16%;
however, there is a tradeoff between the required capital
investment to deploy RESs/BESSs and the amount of cost,
fuel, and emissions savings.

Simulations have demonstrated the effectiveness of BESSs
in mitigating the negative impact of RES fluctuations on system performance. A model of the KLFN microgrid has been
implemented and validated using power systems computeraided design software in a collaboration between the University of Waterloo, Ontario, and the engineering firm Hatch,
Ltd. In the proof-of-concept results presented here, the battery is operated to compensate for wind generation fluctuations, while the 600-kW diesel generator is dispatched
to supply a fixed load, thus leveling the total wind turbine
and BESS power output at 300 kW. Figures 6 and 7 demon-

table 1. The Kasabonika microgrid economic analysis.

Baseline

PV + Wind
+ BESS
+ Diesel

RES penetration (%)

18%

BESS capacity (kWh)

Fuel consumption
(million liters/year)

1.07

0.89

Emissions (metric ton/year)

3.33

2.80

RES capital (CAN$million)

3.35

BESS capital (CAN$million)

0.18

O&M cost (CAN$million/
year)

3.68

3.35

Description
System characteristics

Fuel and emission

Cost

0.7

59.8
59.6
0

(a)

60.2
60

6
t (s)

ieee power & energy magazine

Thermal Energy Storage Systems

Because the KLFN community is located in the northern part
of Ontario, it has significant thermal demand during winters
from space heating, which is currently met mostly by wood
pallets, heating oil, and electricity. If the electricity is generated by RESs, it can be used for space heating to reduce the
use of fossil fuel. As mentioned previously, BESSs require significant capital investments, whereas TESSs are less expensive
ESS options for the efficient integration of RESs that still meet
the large thermal demand. To evaluate the impact of integrating TESSs in the KLFN system, a study was performed for the
period from November 2014 to March 2015 using the actual
measured electricity demand and generation from the installed
september/october 2017

Table of Contents for the Digital Edition of IEEE Power & Energy Magazine - September/October 2017