Ornamental Greenhouse, Genkai Energy Park (玄海エネルギーパーク 観賞用温室)

Visitors have been welcomed beside the Genkai nuclear power station, in the town of Genkai in Saga Prefecture, since 15 April 1973, when the Genkai Atomic Energy Exhibition Hall opened. That first building, with an exhibition room, a viewing deck and a meeting room, received about 2.25 million visitors before closing on 29 February 2000.

The following month, in March 2000, Kyushu Electric opened the Genkai Energy Park in its place. The new site combined a science hall on electricity generation, featuring a full-size reactor model 13 m tall, a pavilion called the Kyūshū Furusato-kan (Kyushu Hometown Hall) and an ornamental greenhouse heated with the power station's waste heat. Outdoor gardens, among them a camellia garden, and a play area complete the complex.

The park draws around 300,000 visitors a year. In a place designed above all to explain energy production, the greenhouse plays a different part: the operator presents it as a space for relaxing amid the scenery, with seasonal flowers. The sources consulted mention neither a renovation of the greenhouse nor the name of its designer.

The greenhouse has one storey above a basement, with a total floor area of about 1,300 m², and rises to a maximum height of roughly 18 m. Its structure is steel, with a glass envelope clad in aluminium. The fully glazed interior is warmed by waste heat from the neighbouring power station.

The space is divided into four zones of distinct character. The tropical house, of 529 m², is built around water features, waterfalls and rockwork. The display house, of 432 m², takes the form of a Mediterranean-style patio with fountains. The rest garden, of 279 m², offers a timber deck with seating, kept comfortable all year by underfloor air conditioning. A small orchid room of 56 m² completes the route.

Outside, a garden takes up the motif of the terraced rice fields (tanada) found in the town of Genkai.

According to the town of Genkai, the greenhouse brings together about 200 species and 16,000 plants from different parts of the world, with orchids to the fore. The tropical house pairs its waterfalls with exotic flowering plants; those named by Kyushu Electric include ōgi-bashō, hōōboku, plumerias, heliconias and the Mickey Mouse tree.

The orchid room shows cattleyas, oncidiums and phalaenopsis among others. Part of the planting is changed with the seasons, so the Mediterranean patio of the display house looks different through the year. The operator's list also names genkai-awayuki, tsuwabuki and hama-nadeshiko.

The greenhouse is seen as part of a visit to the Genkai Energy Park, right next to the Genkai power station on National Route 204. Touring the park alone takes about 70 minutes, and the greenhouse makes a restful, flower-filled pause after the science hall and its full-size reactor model. The camellia garden, the terraced garden and the outdoor play area extend the walk. The site is reached by car from Fukuoka, about 1 hour 10 minutes from the Maebaru-Higashi interchange.