SOLAR WATER HEATERS/GEYSERS
- rentechsyst
- Jul 20, 2020
- 2 min read
Updated: Jul 20, 2024
Ok, so we will dedicate two posts to solar water heating. If you are like me, and cannot stand cold water (even in summer :) ) ...and you are tired of the high energy bills associated with water heating then solar water heating is a good option to consider. Conventional water heating is estimated to consume between 10 to 14% of electricity usage in a residential building [1]; [2] … so going solar will certainly save you some dollars!!
Solar water heaters or geysers basically work by converting sunlight energy into heat using solar thermal collectors. Simply put, a collector facing the sun heats up a working fluid that transfers it into a storage system or vessel, which can then be used later. The “working fluid” can be water with direct heating, or some other heat transfer fluid which then “passes on” the heat to the water in a tank or loop. A solar geyser can be hybrid and combined with either electric or gas boosting.
Low Pressure vs High Pressure Geyser??
Are you wondering which option is best for you between a pressure and non-pressure model?
Low Pressure Geyser
A low pressure geyser operates at low water pressure, with the pressure of the water solely due to gravity (from the height of the tank).
Advantages [3]:
-Simple design, with no moving parts
-Cheaper than pressure geysers
-Longer life-span due to low operating pressures and low stress on tank and collector
-Usually lightweight
Disadvantages:
-Due to low pressure, has limited uses depending on available mounting space.. typically mostly used for residential applications
-Entire solar system needs to be shutoff if just one part of the glass collector breaks
-Usually mounted on the roof.. so extra load for the roof
High Pressure Geyser
A high pressure geyser basically contains your water in a tank under high pressure (your NORMAL tap water pressure). The pressure control valve reduces the cold water pressure to the same pressure of the hot water coming from the geyser, so cold and hot water operate at same pressure.
Advantages:
-Hot water pressure can be quite high
-Works well with pumps
-You do not need to mount the tank on the roof, so looks better
-More robust (strong)
Disadvantages:
-More expensive than low pressure geysers
-There are moving parts, so more maintenance concerns
Next post we look at the critical components of a solar water heater/geyser.
Sources:
About Author:
Lovewell Chitiyo is a Mechanical Engineer with 15 years experience in the building services Engineering consultancy, renewable energy systems and sustainable design fields. He is currently studying Masters in Renewable Energy at Stellenbosch University in South Africa
Lovewell is an Accredited Professional with the Green Building Council of South Africa for Existing Buildings Performance and New Buildings; Interiors, holding several qualifications and certification in Renewable Energy and Sustainability.
Lovewell also has vast experience in design, supervision, installation and commissioning of several projects locally and regionally in the last 15 years.
Comments