Rooftop PV System Policy and Implementation Study for a Household in Indonesia

This paper discusses the recent solar rooftop photovoltaic (PV) system policies in Indonesia, particularly for the implementation of the residential sector. The aim of this study is to demonstrate the rooftop PV system for a household based on the current related policies. The study is conducted by literature reviews and computer simulation for a typical rooftop PV system for residential in Surabaya, Indonesia. The most recent solar energy policy in Indonesia is the Ministry of Energy and Mineral Resources Regulation No. 49, the year 2018, which establishes net metering for the residential, commercial and industrial National Grid (PLN) customers that have excess power from solar rooftop installations. The simulation shows the average values global solar irradiation on a horizontal surface in Surabaya vary between 6.81 kWh/m 2 and 4.82 kWh/m 2 with an average of 5.54 kWh/m 2 /day. Energy output by 3 kWp rooftop PV system in Surabaya is found about 4,200 kWh/year, with an average of 11.67 kWh/day. Economically, under present conditions, rooftop on-grid PV system investment would give about 9-10 years of the payback period.


INTRODUCTION
Solar energy is one of the most promising of renewable energies in attempting to reduce fossil-based fuel consumption due to its limited reserved and the greenhouses gas (GHG) emissions from the combustion process.Indonesia is located around the equator line, which fortunate to have relatively high and stable daily solar energy throughout most of the year.Statistically, the daily solar irradiation in Indonesia would provide more than 500 GW of potential solar sources (Dang, 2017;UNEP DTU Partnership, 2016).However, the solar photovoltaic (PV) sector has not been well tracked in Indonesia.By the time of writing this paper, based on various sources (Hamdi, 2019;Tarigan, 2018;Tarigan et al., 2015), it is estimated that there are approximately 14.7 MW of solar PV system running on-grid, 48 MW under construction, and an estimated 326 MW in the pipeline.This capacity is relatively small in comparing to the neighboring South East Asian countries such as Thailand (2.6 GW) and the Philippines (868 MW) (Hamdi, 2019).
The success of the implementation of the rooftop PV system in and policy or regulation.It is important for electricity consumers the literature regarding the policies that regulate the rooftop PV systems in particular countries.Goel (2016) studied and reported the policies, challenges, and outlook of solar rooftop in India.It is reported that with a strong commitment to increasing the renewable sources based energy capacity to 175 GW by 2022, India has a target to install 100 GW of solar energy capacity.Of this 40 GW would be the share of grid-connected solar PV rooftop (Goel, 2016).Xin-Gang and Yi-Min (2019) studied the economic performance of industrial and commercial rooftop PV in China.
This Journal is licensed under a Creative Commons Attribution 4.0 International License It was reported that for a small rooftop PV investment payback period is short and the risk is low.The levelized cost of electricity is reported at about 0.2727 -0.5573 CNY/kWh.The technoeconomic impact of the rooftop PV system for schools in Palestine schools as the study cases.It is reported that the application of and expanding vastly as an alternative source of energy provider The Government of Indonesian under the Ministry of Energy and Mineral Resources (MEMR) has set a target of 23% of renewable energy of total national energy needs by 2025 (ESDM, 2016).In this connection, the PV rooftop system regulation has recently been introduced (Government of Indonesia, 2018), i.e Permen ESDM or MEMR RegulationNo 49/2018.The regulation allows and encourages users, including residents, public, and commercial buildings to generate electricity by using PV system installed on the building roofs.The produced energy can be exported or fed into the utility grid.
The present paper discusses the current solar rooftop PV system policies in Indonesia, particularly for implementation for the residential sector.The available previous related policies on solar PV system for residential is done using solar PVSpot (SolarGis, 2017).The objective of this study is to demonstrate the rooftop PV system for households based on the current related policies and to The information and the results from this work are expected to be useful for the development of solar rooftop PV system applications for a larger scale in Indonesia, particularly for residential sectors.

METHOD
The study in this present work is carried out by literature reviews and computer simulation.The related solar PV policies documents and literature were retrieved through the internet, and then they were reviewed and discussed.Implementation of solar rooftop PV system for a typical household is simulated by taking Surabaya as object location.
In terms of capacity by the National Electricity Grid (Perusahaan Listrik Negara, PLN), there are several types and sizes of installation capacity for residentials, however, the installation with 1300 kVA and 2200 kVA (BPS Kota Surabaya, 2019) are dominating the houses in urban area such as Surabaya.The amount of energy consumption with these capacities varies between 3 and 15 kWh/day.Hence, the analysis and simulation in this study are conducted for a 3 kWp capacity of the on-grid rooftop PV system, which assumes that it would be able to supply the daily energy demand.Simulation is done using PVspot online software by SolarGIS (SolarGis, 2017).In addition, economic and environmental analysis is carried out using RETScreen (Natural Resources Canada, 2017)

Solar Energy Policies in Indonesia
Since 2013, the government of Indonesia, through the Directorate General of New and Renewable Energy and Energy Conservation (DGNREEC) of the MEMR has started to regulate solar energy Regulation Number 17/2013.In the early years, solar technology was still perceived as expensive and unreliable relative to conventional technologies.This has made the lack of a market for solar energy.
In the course of time, there have been the regulation changes in Indonesia as shown in the road map solar energy policies in Figure 2.

Rooftop PV System Policy
The most recent solar energy policy is in Indonesia is MEMR Regulation No. 49 the year 2018 which establishes a net metering scheme for the customers of PLN, including the residential, commercial and industrial customers that have excess power from solar rooftop installations.Under the regulation, the installation and construction of a rooftop PV system require prior approval and involves application submission to office of relevant PLN distribution unit, along with the required technical information and number, the capacity of the rooftop PV system planned to install, one-line diagram of the equipment to be installed.
Upon customer application, PLN will make the evaluation on the application and notify the decision within 15 business days.The decision can be either approved or rejected.The installation work for the PV system can only be started after a customer gets formal approval.
With the rooftop PV system, the electricity bill for PLN customers will be calculated monthly using the export-import energy meter.The calculation is based on the energy used (kWh import) value minus energy produced by the rooftop PV system (kWh export) value.Under MEMR Regulation No 49 the year 2018, the price of electricity by rooftop PV customers that exported to the grid if a rooftop PV system customer exported 1000 kWh to the grid (daily accumulated for a certain month), and the customer imported 1200 kWh from PLN, the export value will be calculated as 650 kWh.In this case, the customer would be billed for 550 kWh (i.e.650 subtracted from imported of 1200 kWh).Some key points of MEMR Regulation 49 the year 2018 are:  installations, capacity charge and emergency energy charge are exempted, while for on-grid installation will be subject to both charges.
There have been some questions raised related to the latest MEMR Regulation 49/2018, including how the electricity that exported from rooftop PV systems valued by the government, and what is the additional requirements to obtain approval prior to system installation.The multiplier of 65% applied to exported energy is considered unfavorable to rooftop PV users (Hamdi, 2019).

Implementation Study for Household
by many factors, including materials properties and operating environment conditions.The material properties have been environmental operating conditions factors can be simulated to results showed the potential of the site solar irradiation presented in the form daily sum of global irradiation.
The result from the simulation shows that the average values global solar irradiation on a horizontal surface in Surabaya vary between 6.81 kWh/m 2 and 4.82 kWh/m 2 with an average of 5.54 kWh/m 2 /day.The global solar irradiation consists of direct, The monthly global from simulation results is shown in Figure 3.The global radiation in the past time was usually higher during month April -October than the other months due to dry season, meanwhile low radiation during December -March due to rainy season.However, in the present time, the season period is likely unpredictable, and further investigation should be done.Daily air tem perature showed that the ambient temperature in Surabaya varies about 26-30°C.
The results of the simulation on energy output by 3 kWp PV system presented in Figure 4. Total annual energy production from the system is found at about 4200 kWh.The lowest energy production was in December and January which is about 190 kWh.
factors such as dust, shading, weather, etc to optimize the energy output.

Economic Analysis
A quick market survey on the retail price of PV system components in Surabaya was conducted using the internets.There was a brands, types and vendors or suppliers.The average prizes among all surveyed data are used for economic analysis.The retail price of components and cost for installing 3kWP rooftop on-grid PV is presented in Table 2.
Table 3.Assuming that the price of one kWh of exported electricity from rooftop PV     system to the grid is 0.09 (USD/kWh), then during 1 year, based current situation above, the system will be generated earning: 4.200 (kWh/year) ×0.09 (USD/kWh) ×1 (year) =378 (USD/year).Lifetime for PV panels is considered about 20 years, while for inverters are 6-7 years.
Figure 5. ure is from the accumulation of money value of electricity produced by the PV system in comparison to system incremental of installation cost.It can be seen that under present conditions, rooftop on-grid PV system investment would give about 9-10 years of the payback period.

Environmental Analysis
Replacing fossil fuel with renewable ones for power generation would give a positive impact on the environment.It has been known that the combustion process of fossil fuels in power plants would realize GHG such as Sulphur dioxide (SO 2 ), nitrogen oxide (NOx), and Carbon dioxide (CO 2 ) to the atmosphere.Besides, it also produces a large amount of ash that needs particular handling.Mathematically, reducing GHG emissions from using 3 kWp solar panels in Surabaya (due to replace the burning of fossil fuel

CONCLUSIONS
The regulation on solar energy application in Indonesia has been reviewed, and the simulation of the rooftop PV system a typical household in Surabaya Indonesia has been conducted.The most recent solar energy policy in Indonesia is MEMR Regulation No. 49 the year 2018 which establishes a net metering scheme for the customers of PLN, including the residential, commercial and industrial customers that have excess power from solar rooftop installations.Under the current regulation, the electricity bill for PLN customers will be calculated monthly using the export-import energy meter.The calculation is based on the energy used (kWh import) value minus energy produced by the rooftop PV system (kWh export) value.
The price of electricity by rooftop PV customers that exported The simulation shows the average values global solar irradiation on a horizontal surface in Surabaya vary between 6.81 kWh/m 2 and 4.82 kWh/m 2 with an average of 5.54 kWh/m 2 /day.Energy output by 3 kWp rooftop PV system in Surabaya is found about 4200 kWh/year, with an average of 11.67 kWh/day.Economically, under present conditions, rooftop on-grid PV system investment would give about 9-10 years of the payback period.Enviontally, a 3 kWp rooftop PV system would reduce CO 2 emission about 4, 7-ton kg/year.
simulation software.The geographical o o altitude: 3m.The other parameters for the simulation are shown in Figure 1.

Figure 1 :
Figure 1: Simulation parameters for studied rooftop PV system

Figure 2 :
Figure 2: Solar policy roadmap in Indonesia

Figure 3 :
Figure 3: Global irradiation and air temperature in Surabaya

Figure 4 :
Figure 4: Energy output by 3 kWp PV system in Surabaya Figure 5:

Table 1
presents the comparison of solar regulations ever issued in Indonesia.The important issues of regulations are procurement method, residential application, the build own operate transfer (boot) rules, and deemed dispatch in case of force majeure.the rooftop PV system until the latest MEMR Regulation Number 49/2018 was introduced.

Table 4 .
GHG reduction as shown inTable 4 is just representing by applying the PV system by a household.If the number of the house installing PV increases then the amount of reduction GHG should be multiplied by the number of houses with PV systems.