special study - synopsis

8/10/2019 Special Study - Synopsis

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Class project report

TITLE: Study the cooling load Reduction due to roof mounted solar PV

panel and the project evaluation incorporating the associated cooling Load

reduction

By

Index No.

Name

Deadline: 15th October 2014


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TITLE: Study the cooling load reduction due to roof mounted solar PV

panel and the project evaluation incorporating the associated cooling Load

reduction

1. IntroductionHeating, Ventilation and Air Conditioning (HVAC) system is the major energy consumer in

buildings. This energy cost increases as the heat gain increases. Heat gain is two types as

external and internal. Many environmental factors such as sunshine, cloud density, humidity

and wind speed all affect to the external energy heat. External energy comes in to the

building by any heat transferring method (i.e. by conduction, convection, or radiation). When

these factors are considered, suns energy that comes by conduction through roof is

significant. Especially in poorly insulated, single story buildings with large surface area suchas warehouses, most of heat enters through the roof.

Increasing of roof insulation, shading and the albedo (or roof reflection) reduce the cooling

load. Well insulated roof reduces the heat entering to the building by conduction. Shade trees

planted near the buildings results in reduction of cooling energy. Another way to reduce heat

that comes through roof is increasing the reflectance of roof to reflect the solar energy by

increasing reflecting properties of the roof. As an example roof is painted using reflecting

color usually in white. When these concepts are applied to the roof, these roofs are called as

cool roofs. A cool roof can be desirable to a building owner for several reasons such as

reducing of energy bills by decreasing air conditioning needs, improving indoor thermal

comfort for spaces that are not air conditioned, and decreasing roof operating temperature,

which may extend roof service life.

Green Building concepts have been developed as solutions for the energy crisis and as

ecofriendly products. Therefore currently most of building tends to fulfill their energy

requirements in their premises itself using alternative renewable energy sources such as solar

and wind without going to national grid. New energy practices such as net metering systems

also have get popular and they also use solar PV panels. Use of solar panels on the rooftops

helps to fulfill the factors discussed above.

2. Problem Statement

Currently solar panel projects are evaluated only on the grid electricity that has been offset,

and financially the payback periods are over 6 years. One aspect not considered is the cooling

load reduction that a rooftop mounted solar panel brings in. Since the solar panels will


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provide shade to solar radiation falling on the roof, the cooling load is reduced and a study

needs to be carried out to quantify the reduction in cooling load. With the reduction in

cooling load the payback periods of the solar panel is expected to come down. This study

could shed light as to how much cooling load reduction a roof mounted solar panel would

bring in and the project evaluation when cooling load reduction is taken into account.

3. Aim and Objectives

The aim of this research project is to study the cooling load reduction due to roof mounted

solar PV panels and the project evaluation incorporating the associated cooling load

reduction.

Identify the cooling load reduction due to roof mounted solar PV panel

Identify the effect of orientation and the angle of PV panels on the cooling load

Identify the effect of gap between the solar panel and the roof on cooling load

Understand the effect of cooling load reduction as a factor in evaluating of PV panel

project

4. Methodology

Literature survey on relationship of parameters such as roof solar reflectivity,

transitivity etc

Analyzing the documents and identify existing mathematical models connecting to

this heat transfer process

Collecting of roof temperature data from the actual sites (temperature data under PV

panels and exposed roof)

Use of computer based model and doing a simulation on cooling load reduction

Understand the effect of cooling load reduction as a factor in evaluating of PV panel

project

5. Contribution to knowledge

Payback period that is used to evaluate the feasibility of a PV panel project is evaluated

considering only on the grid electricity. Results of this study will add another fact to the

evaluation process of feasibility of PV panel projects. A project that has a higher payback


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period is haply given up. It is in vain if such project is given up even though there are factors

without taking in to account, which reduces payback period. Therefore especially result of

this study will benefit for the both user and promoter. Indirectly the society also gets benefits.

6. Supervisors Approval

I, the supervisor for this project, was given a draft of this document and adequate time to go

through it and suggest changes.

Project Title Study the cooling load reduction due to roof mounted

solar PV panel and the project evaluation incorporating

the associated cooling Load reduction

Submission Date

Student Name/ Index No.Supervisors Name

Supervisors Signature

special study - synopsis

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