Mills in Alto Aragón — central eléctrica


Arrés is easily reached from Jaca. Take the main road to Pamplona. After about 20 km where the road bends right over the bridge (Puente La Reina de Sta Cilia de Jaca), don't turn but continue straight-on towards Huesca. Almost immediately there-after Arrés is signposted. Follow the narrow road for about 3 kms until you notice a patch of trees not too far away to the right. It's before you'll reach the farm houses and the bend towards the village. The mill is in fact two : a harinero, muy ruinoso, and a powerstation with lots of interesting stuff. The mill gets water from the Río Aragón.

Pictures: 17.VIII.2003

(1) The powerstation with overgrown embalse
(2) The dynamo with
voltage controls and switch room

The powerstation is the part best preserved of this site. It's the small building leaning against the bigger harinero. One enters the engine room from a door next to the milling seat of the flour mill. The central eléctrica is divided in two rooms. Coming from the harinero you'll first enter into the engine room with the turbine (5)
The next room is the powerstation proper with a dynamo, a panel with several indicators and a smaller separate room serving as a switch room. The turbine also was regulated from this room (10).

The alternator is a Swedish product and bears two labels.


The first label says:
Westeras - swastica with ASEA - Suecia
Sd. Española
de Electricidad
a Bolas

ASEA is shorthand for Allmänna Svenska Elektrifiska Aktiebolaget. The Spanish branch of the company was established in 1914.

These are the specs of the alternator:
ASEA Westeras Sweden - swastica
3 Phase Synchr. generator
Type6?2? No.422483
Exc. Volts110Exc. Amps6.

(5) Dynamo with
turbine room behind
(6) Control panel
(7) Back-side of control panel

The Swedish ASEA company was established in the late 19th century to commercialize Jonas Wenström's power generation system. It was a three phase AC device and a major improvement compared with the concurrent systems because of the all-in-one construction of engine, generator and transformer and also because of the resulting easier transmission of the AC current against the earlier DC current.

Our maps (ed. 1952) show power lines emerging from this Molino de Arrés and running first towards the village of Arrés then Bailo, Arbués and Alastuey, which is quite something.

The control panel carries several dials, switches, fuses in the upper part and one regulator wheel on the lower part. The wheel features a label telling us to turn left to Raise and right to Lower (Notice the English. In Spain!) This rather modest wheel sits on a huge regulator switch mounted on the back side of the plate. The switch counts many double contact points and runs between on and off.

The label located above the central switch says

Joaquin Guiral
Talleres Electro Mecanicos


The driving force is delivered by a turbine (8) We can appreciate the blades in  9. We've seen several turbines in other watermills, but most were of a different build (e.g. Nocito, Gistain, Acumuer). A belt ran over the huge driving-wheel mounted on the axle of the turbine (See also 5). The turbine was regulated with a rod that could be adjusted by means of a wheel with gauge (10). There is no detailed scale marked on the gauge. The text reads
Constructor de maquinas
Caballos de fuerza
(horse power)
Alabes abiertos
(blades open)
N° Zaragoza 1
The turbine carries two more labels.
The small black one says
José Amoros
The slightly bigger reddish label says
Talleres Martin

(10) Regulator of the turbine
(11) Voltage meter

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