SHI Solar Thermal System Design & Components

Question 1

What is the primary function of a solar collector in a thermal system?

Accepted Answer

Absorb sunlight and convert to heat

Answer

The primary function of a solar collector in a thermal system is to capture solar radiation from the sun. It is specifically designed to absorb this sunlight and efficiently convert the light energy into thermal energy, or heat. This collected heat is then transferred to a fluid, which circulates through the system to provide hot water or space heating.

Question 2

Which component stores heat energy in a solar thermal system?

Accepted Answer

Storage tank

Answer

In a solar thermal system, the storage tank is the dedicated component responsible for holding and maintaining the temperature of the heated fluid, typically water. This allows the system to store the thermal energy collected during sunny periods. The stored heat can then be used later, ensuring a continuous supply of hot water or heating even when the sun is not shining.

Question 3

What is the role of a heat exchanger?

Accepted Answer

Transfer heat between fluids

Answer

A heat exchanger is a device engineered to efficiently transfer thermal energy from one fluid to another without the two fluids physically mixing. In solar thermal systems, it typically transfers heat from the solar collector's heat-transfer fluid (e.g., glycol) to the potable water or space heating fluid. This separation prevents contamination and allows for optimal fluid selection in each loop.

Question 4

Which fluid is commonly used in solar thermal systems?

Accepted Answer

Propylene glycol

Answer

Propylene glycol is a commonly used heat transfer fluid in solar thermal systems, particularly in climates where freezing temperatures are a concern. It acts as an antifreeze, preventing the fluid in the collector loop from freezing and potentially damaging pipes or collectors. Additionally, it is non-toxic, making it a safer choice for systems that might interact with domestic hot water.

Question 5

What type of collector is best for high-temperature applications?

Accepted Answer

Evacuated tube collector

Answer

Evacuated tube collectors are highly efficient and are particularly well-suited for high-temperature applications or colder climates. The vacuum between the glass tubes significantly reduces heat loss through convection and conduction, allowing these collectors to achieve and maintain much higher operating temperatures compared to traditional flat plate collectors. This makes them ideal for demanding heating needs.

(SHI) Solar Heating Installer Certification Practice Test

(SHI) Solar Heating Installer Certification Practice Test

SHI Solar Thermal System Design & Components