Features of Equipment, Systems and Facilities
A 150 kW PV power generation system is installed on filtration
bed of the water treatment plant, and power generated is used
for driving pumps and, in the event of disasters, is used
as emergency power source for supplying drinking water to
120,000 households.
The introduction of this system reduced the power charge extensively.
The triple utilization of PV system for operating the water
treatment plant, for coping with emergency needs, and for
saving electricity cost, as well as the enlightening effects
for citizens were appraised.
Prevention of Algal Proliferation
The explosive proliferation of algae in the trickling filter
reservoir under the direct sunshine is prevented by shading
with PV arrays (PV modules installed on frames).
Utilization as Emergency center
In the event of wide-area disasters, the Water Treatment
Plant with the neighboring Water Purification Plant are
used as a emergency center for about 2,000 persons, and
the PV system supplies energy for lighting and communications
devices, such as TVs and radios.
Water Supply for Emergency
In the event of disasters, water is pumped from the river
into the filtration pond and purified at a rate of 1,200
m3 per day by using PV power generated in the daytime, to
secure drinking water for 120,000 households in the local
area (10 L per house).
Reducing Electricity Charges
As the PV system is introduced, the power-receiving contract
with the utility was changed to a time-zone adjustment contract
for extensive rate reduction, based on the daytime power
demand control. The saving of power charge with the change
of contract and in-house generation will allow to recover
the investment cost in about 12 years.
Specification
| Solar
cell capacity |
150 kW |
| Power
usage |
Power supply for
the plant and, emergency case |
| Systems
type |
Grid connected
system (no reverse currnent) |
| Solar
cell array |
Type |
Polycrystalline
silicon cell |
| Panel area |
1,289 m2 (1,050
modules) |
| Tilt angle |
10 degrees |
| Expected
annual power production |
168,000 kWh |
| Storage
battery |
Type |
Cathode absorption
sealed type (Model MSE) |
| Capacity |
100 Ah (6 V ×
48 cells) |
| Inverter |
Capacity |
10 kW × 13
units,
20 kW × 1 unit |
Power
supply from Kyushu
Electric Power Co., Ltd. |
Type |
Time zone adjusted
contract |
| Peak hours |
500 kW (from 13:00
to 16:00 in summer) |
| Ordinary hours |
830 kW |
 |
 |
Outer view of PV arrays |
Filtration reservoir and PV arrays |
|
