Nipon Ketjoy*, School of Renewable Energy Technology (SERT), Thailand Wattanapong Rakwichian, School of Renewable Energy Technology (SERT), Thailand Vitsarut Wongchupan, Panya Consultants Co., Ltd., Thailand Theerapon Sankarat, Tesco Lotus, Ek-Chai Distribution System Co., Ltd., Thailand Corresponding author. E-mail: ketjoy@yahoo. com

Abstract: This paper presents a technical feasibility study project for the large scale rooftop photovoltaics (PV) grid connected system at Charoenphol-Rama I green building super store of TESCO LOTUS (TL) in Thailand. The objective of this project is (i) to study the technical feasibility of installation 350 kWp PV systems on the top of the roof in this site (ii) and to determine the energy produce from this system. The technical factors are examined using a computerized PVS 2000 simulation and assessment tool. This super store building located in Bangkok, with latitude 14° N, longitude 100° E and the building direction is 16° from North direction. The building roof area is 14,000 m2; with 3 degree face East and 3 degree face West pitch. Average daily solar energy in this area is approximately 5.0 kWh. The study team for this project consists of educational institution as School of Renewable Energy Technology (SERT) and private institution as Panya Consultants (PC). TL is the project owner, PC is responsible for project management, and SERT is a third party and responsible for PV system study, conceptual design and all technical process. In this feasibility studies SERT will identify the most attractive scenarios of photovoltaic cell technology (mono, poly-crystalline or thin film amorphous), system design concepts for owners (TL) and determine possibility of the energy yield of the system from different module orientation and tilt angle. The result of this study is a guide to help TL to make decision to select proper rooftop PV system option for this store with proper technology view. The economic view will not be considered in this study.

Keywords: Rooftop photovoltaic grid connected system, Contractor potential

1. Introduction

PV systems can be installed on the top of the roof or other surfaces of buildings. From the many advantages of rooftop PV grid connected system, more and more countries have set up the target for using PV in household and building sector since PV integration in building surfaces represents a significant progress in urban PV applications.

Tesco Lotus (TL), a subsidiary of TESCO PLC, the largest retail stores chain in United Kingdom, is leader in Thailand with currently 47 hypermarket stores over 500,000 square meters of sales area in 25 provinces around the country. By October 2004 the 50th store in central of Bangkok will be opened. This building so-called "Green building” will integrate various improvement on lower emissions, energy savings and environment. One of the ideas is to integrate the PV rooftop grid-connected system in this building without interrupting other planning schedules. How much energy can be produced per year from the PV grid-connected system which is expected to be installed. Also the module orientation and tilt angle effect to yearly energy yield. In order to know and get the answers to these questions the technical feasibility studies have to be done.

In this paper, a technical feasibility study of PV rooftop grid-connected for Charoenphol — Rama I green building super store of TESCO LOTUS (TL) in Bangkok will be presented.

2. Methodology