Making good use of the natural resources in your home is always a great step towards going green. This is why solar energy systems are among the most sought after types of energy for homes to reduce the reliance on electricity. One major use of energy systems in homes is to provide hot water. Solar hot water systems come in different types including drain-back, loop, and evacuated-tube solar water heating systems. All these types fall in two major categories, which are active and passive solar water heating systems. Knowing a few things about these two categories will help you select the most appropriate solar water heating system for your home.
Cost
Passive solar water heating systems are often less expensive than their active counterparts. In order to circulate water, a passive solar water heating system uses natural convection, so it requires fewer resources to build, operate, and maintain. On the other hand, an active solar water heating system relies on other equipment such as pumps and power blowers to collect the energy from the sun, store it, and convert it to electric energy for use in your home. This extra equipment contributes to the higher cost of the active systems.
Among the extra equipment that come with active solar panels are solar collectors and heat storage units. To accommodate them, you will need to build a heat storage and collector area, which is costlier because a passive system doesn't need those. The higher the number of parts, the greater the level of maintenance required, and the higher the maintenance costs.
Reliability
You need something that will be reliable throughout its service life. The passive system does not require electricity to function. Instead, solar collectors may be placed at specific angles to the sun and filled with water. As the water heats up it flows into a storage tank to be used in your home for showers and other applications. This is reliable in one major way. Your hot shower won't be affected when you have a power outage in your home. On the other hand, an active solar water heating system requires electricity to power the controls and power pumps so you may not enjoy this aspect of reliability when there is no power in your home.
However, since a passive system relies on the availability of the sun, its efficiency is dependent on the weather. Therefore, if you live in a cold area that is prone to freezing temperatures, a passive solar system may not be as reliable.
