Short answer
Greenhouse solar panels in Demre are effective for covering daytime irrigation pump, fan and packing loads. Night heating, however, can be met only with a large battery: 10 kW of heating for 8 hours needs about 80 kWh. So in greenhouse farming, daytime loads are first shifted to the sun; the hybrid and battery decision is made on critical loads. Hail and storm risk must be planned separately.
Key takeaways
- Solar panels cover daytime loads well; they are not a direct solution for night heating.
- In central Antalya, December and January production is 99 kWh/kWp, about 60% of summer production (PVGIS 5.3).
- 8 hours of 10 kW heating needs about 80 kWh of energy; that means a very large battery (example calculation).
- No payment is made for energy fed from the battery to the grid.
- On 4 April 2026, EPDK raised the tariff for agricultural activities by 24.8%.
The most common mistake with greenhouse solar panels in Demre is expecting everything from solar energy. In tomato greenhouse farming, the energy bill is made up of different items: irrigation and fertigation pumps, ventilation and circulation fans, lighting, packing and night heating. Solar panels do not solve all of these to the same degree: they cover daytime loads very well, while the night load can be met only with a battery and at high cost.
This article takes up ways for greenhouse growers in Demre to cut energy cost, load by load: what makes sense to solve with solar, what with the grid, and what with a hybrid or battery? The example calculations are hypothetical; real values are determined by measurement at your facility.
Greenhouse farming and energy load in Demre
Together with Kumluca and Finike, Demre lies in the protected-cultivation belt on Antalya's western coast. Vegetable production, tomatoes above all, is widespread in this area. The energy load varies with the season and the crop calendar: in winter production heating, lighting and humidity control come to the fore; at the beginning and end of summer, ventilation and irrigation load rise.
We do not give a separate PVGIS value for Demre. For neighbouring Kaş, PVGIS 5.3 annual specific production is 1,664 kWh/kWp, and for central Antalya 1,656 kWh/kWp; Demre is expected to be close to these two values. What is critical for greenhouse farming is low winter production: in central Antalya, December production is 99, January 99 and February 108 kWh/kWp. That is, it falls to about 60% of summer production.
Which loads run on solar, and which on the grid?
Classifying loads by how well they suit the sun clarifies the investment decision:
| Load | Time | Fit with solar | Approach |
|---|---|---|---|
| Irrigation and fertigation pumps | Programmable | High | Shift to daytime, directly from panels |
| Ventilation and circulation fans | Mostly daytime | High | Solar + grid |
| Packing and grading | Daytime shift | High | Solar + grid |
| Lighting, humidity control | Night and morning | Low | Grid or battery |
| Night heating | Night | Very low | Another source or a large battery |
The most suitable start is to cover daytime loads. This approach can be done without a battery and with a relatively low investment. For the general load design of greenhouses, you can look at our article on solar energy systems in greenhouses.
Night heating: how far do solar and a battery go?
Night heating is the subject greenhouse growers ask about most. We need to be realistic: solar panels produce by day and cannot directly cover night heating. Meeting electric heating at night means supplying the night load from a battery, and that requires a large battery.
A hypothetical calculation: a heating system running 8 hours through the night at 10 kW of electric heating power needs 80 kWh of energy. With about 90% usable capacity, that means about 89 kWh of nominal battery. This capacity is about 3-6 times the 15-30 kWh batteries in home hybrid systems. Also, to fill this battery every day, extra panels are needed because of low winter production: 80 kWh / 3.2 kWh/kWp per day (December average) ≈ more than 25 kWp of panels may be needed for heating alone.
For this reason, in most businesses it is a more balanced engineering approach to meet heating not from panels but from a suitable fuel or an existing source, and to use solar for daytime loads and daytime pre-heat storage. The choice of heating source is outside the scope of this article; this article covers only the electricity side.
When do a hybrid system and battery make sense?
A battery and hybrid inverter are considered in the following cases:
- If there are critical loads that must run during an outage (humidity control system, circulation, cooler).
- If grid connection capacity is limited and you want to use the daytime surplus at night.
- If there is a steady, small night load (lighting, control panels).
The rule to know in a battery decision is this: no payment is made for energy fed from the battery to the grid. The battery optimises your own consumption; it is not an item to sell. For the structure of a hybrid system, you can look at our article on the hybrid solar energy system.
Complementary ways to cut energy cost
Solar panels are not the only tool. The following steps are also considered to reduce cost:
- Frequency drive: Adjusting the speed of pump and fan motors to need reduces energy consumption.
- LED lighting: Lowers the night lighting load.
- Load timing: Shifting irrigation and packing to daytime uses solar production efficiently.
- Insulation and cover management: Reducing heat loss lowers the heating need.
- Meter and tariff check: Review your subscription type and contracted power.
EPDK (Turkey's Energy Market Regulatory Authority) raised retail sales prices from 4 April 2026; the increase for agricultural activities is 24.8%. Increases like this raise the importance of energy efficiency and own generation. Confirm current tariff values from the EPDK table.
Example: what does a 50 kWp daytime system produce?
Let us take a 50 kWp system for a medium-sized greenhouse business; with 605 W panels this is about 83 panels (50.2 kWp). With the central Antalya PVGIS value, annual production is about 83,000 kWh (50 × 1,656); with the Kaş value about 83,200 kWh. The monthly distribution is as follows:
- December-January: 50 × 99 ≈ 4,950 kWh/month
- April: 50 × 150 = 7,500 kWh/month
- July: 50 × 168 = 8,400 kWh/month
How much of this production will be used at the facility depends on the size of the daytime load. If the facility's daytime consumption is below production, the surplus goes to the grid and is valued only at the active energy unit price; this price is lower than the total unit price on the bill. So installing a system bigger than the facility's daytime load can lower the return per unit of investment. This is an interpretation; for the current form of the rules, check the regulation valid as of October 2026 in the sources at the end of the article.
What is looked at during the survey in Demre?
The following topics are examined at the survey: the condition of the existing transformer and meter, subscription type and contracted power, the distribution of day and night load, the roof or land where panels will be installed, shade sources (greenhouse rows, trees, structures), cable distance and wind exposure. In greenhouse farming the crop calendar is also important: if winter production is heavy and there is a closed period in summer, the annual energy balance is recalculated. That way the system size is built on the annual load curve, not on a single season.
Hail, storm and panel resistance
Together with Kumluca and Finike, Demre is an area where hail, storm and tornado events are recorded. In January 2019 about 1,000 decares of greenhouses were damaged, and in October 2020 Kumluca experienced hail and a storm. We do not give a numerical hail risk, because we could not find a reliable province-level statistic for hail frequency at MGM (the Turkish State Meteorological Service). That said, the 605 W TOPCon panel's datasheet states a wind load of 2400 Pa and a snow load of 5400 Pa; the mounting structure should be chosen taking wind turbulence around greenhouses into account. For insurance cover, you can look at our article on solar plant insurance.
Application, support and the first step
For grid-connected systems, the application in Antalya is made through AEDAŞ's LUS platform (AEDAŞ is the local electricity distribution company). The capacity limit varies by subscription type; for agricultural irrigation subscriptions the twice-contracted-power principle (2022 text) may apply, but the distribution company should be consulted according to your greenhouse's subscription. Ministry of Agriculture Communiqué 2024/15 allows interest-supported loans for renewable energy systems that meet energy needs until 31 December 2026; because we could not verify the rates, we give no figures.
As a first step, you can prepare your last 12 months of bills and your appliance list and request a free site survey through our contact page. For the irrigation side, see our irrigation systems service page.
Conclusion
In Demre, greenhouse solar energy is a strong tool for daytime loads but a limited one for night heating. First classify the loads, shift daytime loads to the sun, calculate the real scale of meeting night heating with a battery, and plan the mounting structure and insurance together against hail and storm risk. That way your expectation is realistic and your investment balanced. Every facility's load profile is different; so rather than applying the calculations in this article one-to-one to your own facility, we recommend redoing them with data measured at the survey.
Frequently asked questions
How much do solar panels for a greenhouse produce per year in Demre?
We do not give a separate PVGIS value for Demre. For neighbouring Kaş, PVGIS 5.3 annual specific production is 1,664 and for central Antalya 1,656 kWh/kWp; Demre is expected to be close to these values. Winter production falls; December and January are at the 99 kWh/kWp level. A site-specific shading and tilt analysis at the survey gives the exact production estimate.
Do solar panels cover a greenhouse's night heating?
They do not cover it directly, because panels produce only by day. Meeting night heating from panels needs a large battery: 10 kW of heating needs about 80 kWh in 8 hours. For this reason most businesses meet heating from another source and use solar for daytime loads. It is possible to store the daytime surplus and carry it into the night, but battery investment grows.
Which solar system suits greenhouse growers better: on-grid or hybrid?
If loads are mostly daytime and an outage is not critical, on-grid may be enough. If there are critical loads that must run during an outage (humidity control, circulation) or if a steady night load is to be met, a hybrid system is considered. The decision is made at the survey with the load list and budget. In both options, the backup load list and budget should be assessed together.
Should panels be installed over the greenhouse or outside it?
Covering the greenhouse cover with panels is generally not recommended because it would reduce the light the crop receives. Roofs of storage, packing and office buildings or open land outside the greenhouse are preferred. Because each site's shading and structural conditions differ, the decision is made at the survey. This choice matters for both crop growth and panel structure.
Does hail damage solar panels?
Hail can damage the panel surface. Mechanical load values are given in panel datasheets (for the 605 W TOPCon model, wind 2400 Pa, snow 5400 Pa). Hail and storm events are recorded in and around Demre; a robust mounting structure and suitable insurance are recommended. We could not find reliable province-level data to give a numerical hail risk. Also, whether the insurance policy includes hail and storm cover should be checked.
What is the solar capacity limit for a greenhouse subscription?
The limit depends on the subscription type. Under the 2022 text, agricultural irrigation facilities can install an unlicensed solar plant up to twice their contracted power; however, whichever subscription group your greenhouse falls into, that rule applies. You should find out the current limit from the distribution company AEDAŞ before applying. This information is valid as of October 2026 and the regulation may change.
How much does solar energy reduce a greenhouse's electricity bill?
We cannot give a fixed percentage for this. The reduction depends on the share of daytime load, system size and self-consumption rate. The effect is greater if daytime loads are high and flexible. For a realistic expectation, a calculation is made at the survey with the last 12 months of bills and the appliance list. Because the calculation also takes tariff and fixed charges into account, results differ from facility to facility.
Sources
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