Short answer
In barns, poultry houses and greenhouses, whether solar energy is suitable depends on the hours at which the loads run. Daytime loads such as fans, water pumps and daytime milking match well with solar. For continuous loads such as a milk cooling tank, night lighting and an incubator, a grid connection, a battery or generator backup is needed. The right system is determined by listing the devices one by one and writing down their operating hours.
First make the load list
The first step in designing a solar system for a farm is not choosing panels. First write every electrical device on a sheet of paper: its power, how many hours a day it runs and at what hours. The device's label shows a watt or kW value; if it does not, it is calculated from the amp and volt values.
This list shows two things. The first is the total daily energy need. The second is the total power of devices running at the same time, that is, the load the system must carry at once. If the morning milking machine, the milk tank compressor and the water pump start at the same time, inverter is chosen to cover this total. Motorized devices draw much more current at start-up than the power on the label; this starting current is also taken into account.
When the load list is made, an unexpected consumer is often found. An old water heater, a floodlight left on all day or an inefficient fan can make the solar system bigger than necessary. Reducing these loads first and then sizing the system costs less.
Which loads match well with solar?
Solar produces most around midday, and in a Şanlıurfa summer midday is when animals are most affected by the heat. In barns and poultry houses, ventilation fans, cooling systems and misting pumps run exactly at these hours. This match makes solar attractive for livestock farming.
Loads that match well with daytime solar are:
- Ventilation fans and exhaust fans
- Misting and cooling pumps
- Water well pump and drinking-water tanks
- Feed mixing and grinding machines, if run during the day
- Greenhouse irrigation pump and fertilizing system
- Milking done during the day
Expert note: Move flexible loads to midday. Running the feed mixer or the tank-filling pump when the sun is overhead instead of early morning reduces the need for a battery or the grid.
Night and continuously running loads
The milk cooling tank runs from the moment milk arrives and keeps cooling through the night after the evening milking. In poultry houses a night lighting program, and in hatcheries continuous operation of the machines, is required. These loads need energy during hours without sun as well.
In this case there are three options. If there is a grid connection, the system is installed grid-tied: solar runs by day and the grid by night. If there is no grid, a battery is added and part of the energy produced during the day is stored for the night. The third option is a generator; it steps in when solar and the battery are not enough or during long cloudy spells.
It is good practice to put loads that cannot tolerate an outage on a separate line. The incubator and the milk tank are fed from the battery and inverter, while loads that can wait, such as a feed machine, can run only when the sun is out. This way the battery capacity is not chosen larger than needed.
Grid-tied, battery, or hybrid?
If the farm has an electricity subscription and the line is reliable, a grid-tied system is the simplest solution. With no battery, maintenance is low. However, when the grid goes down, a grid-tied inverter shuts itself off for safety, and the farm is left without power even if the sun is out.
If outages are frequent on rural lines, a hybrid system is worth considering. A hybrid inverter works together with the grid while it is available, and when an outage occurs it keeps feeding the selected loads from the battery. For a business with loads such as a milk tank and an incubator, this prevents product loss during an outage.
In highland pastures or remote land with no grid at all, a stand-alone system with a battery is installed. In this system the battery capacity is chosen according to how long you need to get through the longest cloudy period. The battery must be protected from heat; a battery sitting in a container in the sun wears out much faster than one in a cool room.
Points to watch in greenhouses
In greenhouses the biggest energy item is often heating, and covering electric heating with solar panels is not economical in most cases. The heating need appears on winter nights, when the sun is at its weakest. In greenhouses, a solar system is used mostly for irrigation, fertilizing, ventilation, and climate control automation.
Installing panels on the greenhouse roof reduces the light the plants receive. For this reason panels are usually installed next to the greenhouse, in a place where their shadow does not fall on it. Humidity and fertilizer vapor inside the greenhouse are harmful to electrical equipment; the inverter and panel board should be kept outside the greenhouse, in a dry place.
How does a barn environment affect electrical equipment?
In barns and poultry houses, ammonia, humidity, and dust are all present together. This environment rusts metal connections, oxidizes connectors, and fills panel boards with dust. The inverter, battery, and panel board should be placed in a ventilated, dry room separate from the area where the animals are kept.
Cables must run at a height the animals cannot reach and inside protective conduit. Rodents damage cable insulation; using conduit and pipes reduces this risk. Grounding is as important for animal safety as for human safety in an environment where animals come into contact with water and metal surfaces, and it should be verified by measurement.
In ground-mounted installations the panel field is fenced. Animals rubbing against the panels or hitting the mounting structure harms both the equipment and the animal.
Prepare before asking for a quote
Prepare the device list with power ratings and operating hours, the last year of electricity bills, how often grid outages occur, and the size of the area where the panels can be installed. The solar calculator on our site gives a first idea based on your monthly consumption; the exact size comes from the load list and a site inspection.
If a well is used, the well depth and pump details are also taken into account. For cases that require licenses and permits, consult the relevant authorities.
Frequently asked
Can a milk cooling tank run on solar energy?
It can run on solar during the day, but the tank also cools through the night after the evening milking. For the night, grid, battery or generator backup is needed. Which is suitable depends on how often outages occur and the tank's power.
Does it make sense to run poultry house fans on solar?
Fans run most in the midday heat, so they match well with solar production. If some fans must also run at night, grid or battery is planned for that part.
If solar panels are installed on a greenhouse, are the plants affected?
If panels are installed on the greenhouse roof, the light the plants receive decreases. That is why panels are usually installed beside the greenhouse, so that their shadow does not fall on it.
Let's draw up your farm's load list together
Share your devices and operating hours; Desa Bilişim will inspect your farm on site and present the suitable system with a written quote.
