The University of Pretoria has recently implemented a sustainable solar heating solution on its campus, making it the largest solar thermal system in the southern hemisphere.

This installation, carried out by Henan Hollam, consists of a single glazed collector system with an area of 700 square meters and storage tanks with a capacity of 40,000 liters.

The purpose of this system is to provide continuous hot water for the students, aligning with the university’s sustainability goals and promoting the use of renewable energy sources.

What is it?

The solar heating system at the University of Pretoria is a sustainable solution implemented to meet the continuous hot water demand of the students. It consists of a single glazed collector system with an area of approximately 700 square meters and storage tanks with a capacity of 40,000 liters.

This system offers several benefits, including reduced reliance on conventional energy sources, lower carbon emissions, and alignment with the university’s sustainability goals. Additionally, the system serves as an educational tool for promoting renewable energy and supports the objectives of the Soul Train Awareness Campaign.

However, the implementation of this sustainable solar heating solution also comes with its challenges. During the summer season, when the campus is empty, the system needs to handle energy loads without consumption, leading to stagnation and the formation of vapor. Furthermore, the campus design required extensive pipe work installation, which raised architectural considerations.

Despite these challenges, the system has proven to be durable, reliable, and capable of meeting the hot water demand of the students effectively.

Installation Details

Henan Hollam installed the largest solar thermal system in the southern hemisphere at the University of Pretoria, specifically at the Honest-to-Put Residences.

The installation posed certain challenges. One challenge was the need to handle energy loads during the summer season when the campus is empty. Stagnation occurred in the system during this period, leading to the formation of vapor.

Another challenge was the campus integration, as the buildings were aligned true north for optimal solar orientation. To extend the campus, a network of circulation pipes was installed, which required discussions on the architectural impact. Approximately 2.85 kilometers of pipe were installed, with some sections going underground.

Despite these challenges, the installation successfully addressed the continuous hot water demand of the students and contributed to the overall sustainability goals of the university.

Panel Configuration and Flow

Panel configuration and flow in the solar thermal system at the Honest-to-Put Residences at the University of Pretoria is optimized for efficient water heating. The panels are arranged in four big arrays, divided into multiple banks, allowing for both series and parallel flow configurations. This configuration maximizes panel efficiency and ensures optimal water flow within the panels.

The system follows a low flow concept, gradually heating the water from 20 to 60 degrees Celsius. This approach reduces the need for larger pipes and improves overall system efficiency.

The choice of flat plate collectors over vacuum tubes was driven by cost-effectiveness at the required temperature range of around 60 degrees Celsius.

The panel configuration and flow design, along with the low flow concept, contribute to the system’s ability to effectively meet the hot water demand of the students while minimizing energy consumption.

Cost-effectiveness and Efficiency

Cost-effectiveness and efficiency are crucial factors to consider when designing a solar thermal system.

In the case of the solar heating installation at the University of Pretoria, flat plate collectors were chosen over vacuum tubes due to their cost-effectiveness in the required temperature range of around 60 degrees Celsius. The radiation levels at the Honest-to-Put Residences make flat plate collectors the cheapest option.

The system utilizes small pumps that run continuously, contributing to the overall energy load. The energy consumption of the pumps needs to be calculated in the overall system, and the current system operates with 80-watt and smaller pumps. However, despite the energy load contributed by the pumps, the energy efficiency of the system has improved compared to previous installations.

To determine the cost-effectiveness of the system, a cost-benefit analysis considering the initial investment, operational costs, and energy savings would be necessary.

Durability and Environmental Benefits

The longevity of the solar heating system at the University of Pretoria has been proven through its four years of operational success, demonstrating its durability and reliability. This sustainable solution has brought numerous benefits to the campus and has had a positive impact on student living.

By reducing reliance on conventional energy sources, the solar heating system contributes to the university’s sustainability goals and helps to reduce carbon emissions. Not only does it provide continuous hot water for the students, but it also serves as an educational tool for promoting renewable energy.

The system aligns with the Soul Train Awareness Campaign’s objectives and showcases the university’s commitment to environmental stewardship. Additionally, the consistent performance of the system over the years has ensured that the students have access to a reliable and efficient source of hot water, enhancing their overall living experience on campus.

Frequently Asked Questions

How does the solar heating system handle energy loads during the summer season when the campus is empty?

During the summer season when the campus is empty, the solar heating system manages energy loads by experiencing stagnation, resulting in vapor formation. This process does not consume energy and therefore has no impact on utility bills.

What is the orientation of the panels and how does it affect their performance during different seasons?

The orientation of the panels, which are aligned towards the winter months and relatively steep, impacts their performance during different seasons. In winter, the panels receive optimal solar radiation, while in summer, the panels experience stagnation and reduced energy production.

Why were flat plate collectors chosen over vacuum tubes for cost-effectiveness in this installation?

Flat plate collectors were chosen over vacuum tubes for cost-effectiveness in this installation due to the temperature range required for the system, as well as the radiation levels in Honest-to-Put. Flat plate collectors are more cost-effective than vacuum tubes at this temperature range, making them the cheapest option.

How does the system utilize small pumps and what is their energy consumption?

The solar heating system utilizes small pumps with an energy consumption of 80 watts or smaller. These pumps contribute to the overall energy load of the system, and their efficiency has improved compared to previous installations.

How has the solar heating system contributed to the university’s sustainability goals and the reduction of carbon emissions?

The solar heating system at the University of Pretoria has contributed to the university’s sustainability goals by reducing reliance on conventional energy sources and lowering carbon emissions. The system has achieved significant savings and has had a positive environmental impact.