SUNNY HIVE is currently the most effective means of controlling Varroa and Tropilaelaps mites without the use of any chemical acaricides. It suppresses and destroys both the brood of mites and the mites themselves in sealed brood cells of bees. This effect is achieved by maintaining elevated temperatures in the brood area of the nest, which are lethal to the young mites and eggs. These temperatures in the solar hive are achieved by heating the interior of the hive by collecting solar energy and converting it into thermal energy using special heating elements inside the hive.
Since it utilizes solar energy, the hive only operates in the presence of solar light and a certain outdoor temperature. This combination allows the temperature inside the bee nest to reach a range of 36-43°C, which is lethal to the mites eggs. The higher the internal temperature in the bee nest within the specified range, the more effective the suppression of mite population growth.
Higher temperatures, especially those lasting for a long time, can be dangerous for brood and queens. This is precisely what limits the hive's ability to operate in extremely hot conditions. However, it's important to understand that SUNNY HIVE is not an automatic system that maintains the required temperature (otherwise it would cost several times more). It's a conventional hive, which requires the beekeeper's attention during extreme weather conditions.
So, let's look at the temperature distribution for the period April-September 2025 in one of south regions (Fig. 1):
• April.
Temperatures in April do not reach 22°C (72°F), which is together with sun
light, is sufficient for the hive to function, meaning the bee nest reaches
temperatures above 36°C (96°F). However, sunny days at these temperatures
improve the hive's temperature and free up some bees from heating the nest
during the day, reducing wear and tear and freeing them up for nectar
collection.
• May. In
May, there were three temperature intervals during which temperatures in the
bee nest reached 37-40°C (98-104°F), allowing for a fairly effective effect on
young mites and eggs. One of the intervals lasted 8 days, which should have had
a very noticeable effect on young mites and eggs.
• June. In
June, temperatures suitable for effective and complete suppression of mite
population growth persist for almost the entire month. Two short, one-day
intervals with high temperatures would have effectively killed off young mites,
which had been greatly weakened during the month, and their eggs in the capped
brood. 47% of sunny days means there were plenty of days for the bees to rest
from the high temperatures and for the queens to continue laying eggs.
• July.
July's conditions—most days with temperatures above 30-36°C and 66% of sunny
days—mean it's best to completely cover the hives with sunscreens and, if
possible, provide additional shade. Conditions for mite breeding at this time
are already unfavorable. The goal of this month is to avoid harming the bees by
overheating the brood and, most importantly, the queen.
• August.
In August, conditions are roughly 50/50... That is, half of sunny days are too hot to open the hive, and
half of sunny days are around 30°C, which is generally suitable for hive
operation and successful suppression of the mite population. In these
conditions, everything depends on the beekeeper. If he wasn't afraid of work,
the hive could be exposed to sunlight for 8-10 days this month, effectively
controlling mites. However, on the remaining days, the screens had to be closed
and perhaps additional shade was required, as temperatures were too high.
•
September. September conditions, except for the first 2-3 days and the end of
the month, were quite suitable for the SUNNY HIVE's operation and suppressing
the development of mites and their young ones in the brood. The hive didn't
require any special attention throughout September, other than the first 2-3
days.
Figure 1. Temperatures and sunny days in Maykop
(Russia), 2025
(The yellow
areas on the graphs indicate temperature zones where, in the presence of
sunlight, the development of Varroa and Tropilaelaps mites is partially
suppressed. The red areas on the graphs indicate temperature zones where, in
the presence of sunlight, the development of Varroa mites is effectively suppressed and
Tropilaelaps mites are destroyed. The dark gray areas on the graphs indicate
temperature zones where, in the presence of sunlight, conditions in the bee
nest can become dangerous for brood and queens.)
I'd like to once again explain to beekeepers of the southern regions who constantly complain that now, during incredibly hot summers, the bees crowding outside the hives even without the use of SUNNY HIVEs... Dear colleagues, the purpose of SUNNY HIVE is to create elevated temperatures in the bees' nest when such conditions are absent in nature! This means avoiding placing of SUNNY HIVEs in the sun and opening the heaters on days when temperatures exceed 30-32°C and the sun is shining. During these periods, nature itself suppresses mites. A Solar Hive should be in operation in April, May, June, and September. It's possible, with supervision, that it can operate partially in August. However, it definitely cannot and should not operate in July. During this time, it should be closed and shaded, like all other types of hives. It's precisely during the "cool months" that a Solar Hive can create unbearable "summer" conditions for young mites and eggs. And thanks to this it can suppress Varroa mites development, completely or partially destroying the mites egg production. This is the SUNNY HIVE's job during the spring and summer season in southern regions. Roughly speaking, it operates in the spring and fall and rests in the summer. It is during these months that mite populations in southern regions experience their greatest growth, and it is during this cool period that the Solar Hive must operate, suppressing their growth.
In more
northern and cooler regions, SUNNY HIVE can operate all summer, with the
exception of some sunny weeks with temperatures exceeding 30°C.
