ZEMCH 2019 International Conference Proceedings April.2020 | Page 438
1. Introduction
With increasing interest in zero‐energy buildings, which minimize energy consumption in
buildings, battery energy storage systems (BESS) along with renewable energy systems are also
attracting attention for their efficient energy management. Among renewable energy systems,
photovoltaics systems (PVs) are most commonly installed in buildings to reduce energy consumption.
However, PVs have a disadvantage in that they supply power only during solar radiation time. By
integrating BESS, PV power can be stored and supplied at other times [1]. In particular, the market for
residential BESS is expanding internationally with regards to zero‐energy buildings. North America,
Europe, and Japan offer a variety of benefits, such as subsidies and tax reductions for the residential
BESS. In addition, TOU (Time‐of‐Use) pricing and RTP (Real‐time Price) can be applied to the
residential electric rate. However, there is no market for residential BESS in Korea yet because of the
high price of residential BESS, low electric rate, progressive rate system, and limited PV capacity [2].
The residential BESS used overseas is for detached houses and requires 1–3 kW PV capacity. In contrast,
most residential houses in Korea are apartment houses. Individual households of apartment houses
use a veranda PV, and not a rooftop PV. Therefore, BESS implemented overseas cannot be readily used
in Korea. Nevertheless, residential BESS can be used with veranda PV of small capacity.
For the operation schemes of residential BESS with PV, Ratnam organized the optimization
approach methods for the scheduling of BESS with residential PVs to assess the customer benefit under
incentives, such as time‐of‐use (TOU) pricing, feed‐in‐tariffs, and net metering [3]. Hassan developed
a model to optimize FiT (PV generation and export tariff) revenue streams of PVs with BESS and
simulated it as residential data [4]. However, the operation scheduling of BESS is determined by the
electric rate for incentives, which do not exist in Korea. Similarly, studies on the schedule and economic
analysis of residential BESS have been conducted [5‐6]. However, studies considering the conditions in
Korea are insufficient.
This paper presents optimal operation schemes of residential BESS with veranda PV for individual
households of apartment houses in Korea. An experiment on various operation modes was conducted
in a demonstration house. The results of this experiment show that some functions need to be added
for residential BESS to be made applicable to individual households of apartment houses in Korea.
2. System Configuration
BESS connected with PV consist of a battery pack, PCS (Power Conversion System), BMS (Battery
Management System), and PMS (Power Management System). Residential BESS installed in a
residential building are typically connected to the PV module, with the load and grid as shown in
Figure 1 [7]. In particular, as this load is a battery load separate from the grid, the battery discharge
power is supplied only to the home appliance connected to the load line. The load is supplied with the
PV or battery power, and the remaining PV power can be stored in the battery and supplied at the
required time.
As mentioned earlier, Korea has many apartment houses and the PV capacity that can be installed
in individual households is limited. The capacity of the veranda PV is about 300–900 W with 1–3 PV
modules connected in series [8]. Therefore, BESS should be designed and operated in consideration of
the environment used. The operation mode of the commercially available residential BESS can basically
charge the battery with PV power and the PV power can be set preferentially to either load or battery.
The battery charges the battery with grid power when the battery is in system check or the SOC (state
of charge) level of the battery is at an emergency level.
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ZEMCH 2019 International Conference l Seoul, Korea