Solar pumping system

Solar pumping: how renewables will ensure water supply anywhere

Solar pumping is the ideal solution to solve problems of water supply, extraction and pumping even in remote places

Solar pumping is a particular technique that allows water extraction by drawing it from the subsoil using photovoltaic solar energy.

The main goal is to supply water anywhere, even in those places very distant from main waterways and to the most isolated communities.

This type of system can be used in various sectors, such as:

  • residential
  • irrigation – agriculture
  • breeding
  • craft activities
  • industrial
  • fire fighting
  • water depuration.

Benefits of solar pumping

This system is particularly suitable in areas where water resources are not immediately available or accessible, or in agricultural areas and in the most isolated or remote areas where it is not possible to build adequate networks and infrastructures.

The increased popularity of Solar Pumping in many areas worldwide is, at the same time, reducing the use of diesel-based systems. In fact, diesel generators, which are expensive due to the cost of fuels, difficult to maintain and extremely polluting, have been widely used so far in isolated places for supplying pumping systems.

Solar pumping using renewable and 100% green energy source cuts down the use of fossil fuels with high CO2 emissions, in compliance with the international agreements of Paris.

Benefits of using a Solar pumping system can be summarized as following:

  • there are no costs for fuel, as it uses daily sunlight
  • it has a long operational life
  • it is a highly reliable and durable system
  • it is easy to use and maintain
  • return on investment is guaranteed
  • it is eco-friendly.

Here is a video showing what solar pumping is.

How does a solar-powered pumping system work?

In a solar pumping system, solar energy converted into electricity starts the motor pump unit which in turn draws water from a well, stream, pond or lake. The pumped water is then fed into a storage area, usually located at a certain height (dam, cistern, tank, etc.), from which it will be redistributed by gravity.

Water requirement and pumping system

The choice of the pump type will depend on the use and the sector where it will be employed. Generally, there are three types of pump:

  • borehole pumps – the most suitable for deep water extraction, as in the case of a well
  • surface pumps – suitable for simple irrigation
  • circulating pumps – to circulate water, for example in the case of pools purification.

To verify the correct sizing of the pumping system it will be necessary to analyze and understand needs in terms of water consumption and sector of use. A large-scale pumping system for irrigation purposes, for example, will require a different system, and perhaps a more powerful one, than one for domestic use.

In some sectors, as in the agricultural field, it will also be necessary to evaluate climate factors, which can greatly influence the water requirement based on the seasons.

Solar radiation

Everything originates from solar radiation hitting the panels and that can be distinguished in:

  • direct radiation –is the solar radiation that reaches the photovoltaic module directly and have their maximum value when they are perpendicular to the module surface
  • diffuse radiation – is the solar radiation reflected and partially absorbed by water vapor, as in case of a cloudy day, which in any case affect the individual photovoltaic module
  • reflected radiation – is the solar radiation scattered from the earth’s surface. The radiation reflected from the surfaces adjacent to the system, which in any case affect the photovoltaic field.

It goes without saying that it is very difficult for a photovoltaic module to remain completely inactive during daylight hours, regardless of weather conditions, since there will always be a minimum of radiation feeding it.

However, you must consider that photovoltaic systems, wherever they are installed, always require a minimum of maintenance, consisting mainly of periodic modules cleaning.

pumping water using solar energy

Operating scheme of a solar pumping system

Power systems

Once the pumping system has been established together with its size (capacity), we will be able to verify how much energy it consumes and therefore it will be possible to design the photovoltaic system appropriately to satisfy the required electricity demand.

Some power systems may be in:

  • alternating current – conversion of the current developed by the photovoltaic cell (direct current), thanks to a DC / AC inverter. The use of the alternating pump power supply method, through the static converter (inverter), acts as an automatic transmission, allowing the pump to start and operate in low light conditions, in case of cloudy, early morning or evening.
  • direct current – the direct current supply can take advantage of the direct connection to the photovoltaic system and, in the eventuality, also obtain energy in the night period, provided by a properly sized storage system.
solar water pumping system for agriculture

Pumping system for agricultural use

There are two types of solar pumping systems:

  • systems that are separated from the home network and independent (stand-alone). An “isolated” system, also known as “off-grid” system, could be more economical and efficient if the use of Solar Pumping is required on areas that are poorly electrified, or difficult to reach.
  • systems that are connected to the electricity grid (grid connected). This is a system that has major advantages because it guarantees self-sufficiency of the irrigation system and the use for other purposes (fire-fighting, washing, etc.) where a photovoltaic system has been installed. Obviously, this is only possible in case of pumping systems adjacent to electrified / built-up areas.

Photovoltaic design software for grid-connected systems

Solarius-PV is a software solution by ACCA software for solar PV systems design and financial analysis of photovoltaic systems of any type and size.

The solution that you can use in all kinds of situations and for every type of need:

  • for installations on new or existing buildings and for large systems (photovoltaic farms)
  • in every location (geolocation with reference climate data)
  • in any boundary condition (near and far obstacles)
  • all types of panels and inverter (archive supplied with thousands of different models)
  • the advantage of 3D modelling (even starting from DXF / DWG drawings or IFC BIM projects).

With Solarius PV, use 3D objects to quickly model the building’s volume footprint, define the PV field installation surfaces and the presence of any obstacles present (chimneys, roof dormers, pylons, etc.) even without any further graphical support.

It doesn’t matter how complex the building is since you can model any type of situation directly in 3D starting from project files in DXF / DWG format or from a BIM model.

Solarius PV takes into account solar shading caused by the presence of long-distance obstacles (mountains, hills, buildings, trees, etc) through a simple photographic survey and directly on the installation site’s solar diagram.