Arch of Time
First conceptualized as an entry to the 2019 Land Art Generator Initiative (LAGI) design competition, The Arch of Time was chosen by the City of Houston out of a shortlist of design concepts in the LAGI portfolio to be implemented at full scale.
The design of the artwork is inspired by the sundial, the oldest known device used to measure time based on the sun's apparent position in the sky. The artwork deviates from the typical sundial configuration by reversing the role of the gnomon, which traditionally casts shadows. Instead, the time of day is indicated by sunlight projected onto the ground through a series of openings on the surface facing south. This surface is covered with photovoltaic modules capable of generating renewable energy.
The sculpture's shape is defined by the diurnal motion of the sun in the Houston sky throughout the year. The path that the sun traces in the sky has been enlarged around noon and tapered at sunrise and sunset. This configuration optimizes the exposure of the photovoltaic cell surface by increasing it during the peak sun hours.
The operating principle of the artwork involves displaying different hours through sunlight cast in the form of abstract symbols representing the face of a clock. Solar noon is depicted by a full circle of sunlight projected onto the ground. The hours before and after solar noon are represented by a growing circular sector within the circle, extending towards sunrise and sunset. To differentiate between the hours, various shades of color reminiscent of the sky are utilized. Colored glass filters, ranging from pink to blue, filter the sunlight to create this effect.
In the East/West section, adjacent sets of louvers spaced 15° apart allow sunrays to pass through dial-shaped openings every hour. Eleven sets of parallel louvers, each oriented towards a specific sun hour, permit sunlight to pass through for a single hour while shading all other inclinations. The sunlight shines through the louvers for less than 60 minutes or 15° (360° / 24h = 15° / 1h). The length of the louvers is determined by the sunlight's inclination, ranging between -7.5° and +7.5°. This configuration turns the sunlight on and off on the ground of the park, precisely within the shadow cast by the arch.
In the North/South section, the shape of the openings is defined by the solar declination, ranging from the angle of the Summer solstice to the angle of the Winter solstice. The Equinox line is perpendicular to the photovoltaic surface. The openings indicating the time are shorter than the parallel louvers, allowing the sun rays to illuminate the hours at all angles of incidence from solstice to solstice.
The new public sculpture welcomes both locals and visitors, establishing itself as a prominent destination within the city of Houston. Through the apparent movement of the sun in the sky, the artwork activates the space with vibrant light and colors, engaging viewers and involving them in the creation of the work through their presence.
This sculpture serves as a practical and playful illustration of the movement of the Earth around the sun. In addition to captivating visitors, Arch of Time integrates renewable energy generation with public space and everyday life in the Second Ward. Inspired by science and powered by renewable energy, the artwork serves as an ideal bridge between art and technology, promoting educational purposes while enhancing the quality of the public space. Furthermore, during nighttime, the space can be utilized as a stage for outdoor public events.