How to make a solar powered garden fountain

Things to be considered when selecting pumps and solar cells for solar-powered garden fountains.

Water-based features have become very popular landscape fixtures, and an increasing number of people’s yards feature a pond or a fountain. Obviously, if your landscaping requires flowing water, some kind of a pump is going to be needed, and that pump will require a power source. It’s possible to simply run an electric line from the house or garage, but you may not want to do that – either because of distance from the house, or because of environmental concerns and the wish to use a non-polluting power source. Solar energy is one possible power source for a fountain.

It is possible to purchase kits for solar powered fountains, ready to install and containing all the components you need. You may not find a kit that you like, though, and while it makes things easy it isn't the only way to obtain a solar fountain. You can select the pieces you need separately. If you decide to buy the components separately and assemble your own, you’ll need to consider several things.

Your first choice will be the fountain itself. You may want to have a freestanding fountain, or perhaps it’s part of a pond or some other large display. In either case, there are a wide variety of choices available at home improvement superstores, some local hardware stores, and on-line. Prices range from under R 200 to over R 3 000, depending on the size and type of fountain desired. If you’re really ambitious, you could design and build your own fountain, purchasing all the individual components and routing the interior plumbing yourself. If you purchase a fountain from the store, it will often come with an appropriate pump. If you design your own, your second choice will be the pump.

The science and engineering surrounding pumps are complex, but you don’t need to be a technical expert to select a pump for your fountain. You do need to take careful note of your requirements. The first requirement, of course, is that the pump must be totally submersible. You will also want a pump with a filter, to avoid damaging it with dirt and debris that will get into the water. The next two fundamental requirements are the amount of water you want to lift and how far you want to lift it. If you’ve purchased a fountain and need to select a pump, then it should tell you what the flow rate (the amount of water) is, and you can simply take out a ruler to measure the height that you’re lifting the water. If you’re designing your own fountain, you can certainly figure out easily enough what the height is, but the flow rate might be a little trickier. Too low of a flow rate, and your fountain becomes a stagnant pool and breeding ground for mosquitoes; too high of a rate, and you have a rushing torrent instead of a relaxing ornament. Rather than trying to calculate this, you may want to look at similarly sized fountains at your local store and see what their flow rates are. Some typical fountains specify a flow rate of 90-140 liters per hour, though there are some that are designed for up to 300 liters per hour. Once you know the flow rate and the amount of lift, you can check out pumps at your local hardware store or on-line and see which ones would suit your needs. You may, in some cases, be able to buy a solar-powered pump, in which case you’re now ready to start putting things together – you have all of your components. Otherwise, your next step will be to select the solar panels to power the system.

Solar power, like pumps, is a highly technical and complex field, but you don’t need to be intimidated by this either. It isn’t necessary to study the theory of photovoltaics in order to buy a solar panel for your fountain, though you do need to pay careful attention to the electrical requirements of your pump. First of all, you need to know what the power requirement (typically expressed in watts) is. This will vary depending on the pump selected. A pump that lifts water a greater distance, with a greater flow rate, will naturally require more power to do so. Power alone isn’t enough, though. You will want to make sure all of the electrical specifications are what the pump needs. This should be clearly noted in the documentation that comes with the pump. If it’s designed to be plugged into normal household current, then it will require 60 Hz AC (alternating current). The amount of current drawn could vary, though if it’s designed for normal household power then it would have to be low enough not to blow fuses or trip circuit breakers. If the pump is designed to run off of a battery, then its requirements will be different. In any case, you’ll want to read over the details for the solar cells carefully to make sure that you get any necessary adapters or inverters to plug into your electrical system.

Once you have the appropriate pieces for your system, the final step is to assemble them. While the choice of location for your fountain is purely a matter of personal preference, the exact location and orientation of your solar panels should be based on where they will get the best sun exposure. A solar panel that’s always in the shade can’t produce as much power as one that’s in the open, exposed to full sun, so you’ll want to place your panels where they’ll get as much sunshine as possible.

Once you’ve got everything purchased and assembled, and your solar panels are in place, turn the system on and enjoy your fountain!