RENEWABLE ENERGY CONVERSION SYSTEMS

MICRO-HYDRO-POWER STATION FOR THE CONVERSION OF FLOWING
WATER KINETIC ENERGY INTO MECHANICAL OR ELECTRICAL ENERGY

Description

Micro hydropower stations are utilized to satisfy the
energy needs of decentralized consumers without

building dams

.

The proposed micro hydropower sta-

tion operates on the basis of the principle of flowing

water kinetic energy conversion into mechanical or
electrical energy. On the basis of the carried out theo-

retical research and undertaken computer simulations

the conceptual diagram of micro-hydro-power stations

with pintle and blades fixed on vertical axles has been

elaborated. The conceptual diagram of the micro hy-
dropower station is based on the conversion efficiency

increase (Betz coefficient) by utilizing the hydrody-

namic effect of the blades and by orientating the

blades towards the water stream in optimum positions
from the point of view energy conversion. On the ba-

sis of this conceptual diagram the pilot-station of the

bi-functional micro hydropower station (fig.1) has

been elaborated. Blades positioning mechanism will

provide for their optimal position dependent on the
water streams in any phase of rotor rotation. The rotor

with hydro-dynamic profile blades, precessional multi-

plier, impeller pump and electrical generator are fixed

on the housing made from a metal framing. The fram-
ing, in its turn, is mounted on four landing pontoons.

The communicating bridge and the mode of fixing to

the bank by cables allow the pilot –station to float de-

pending on the changing level of flowing water. The

pilot-station will serve as site for experimental research
on more technical solutions and working elements in

natural conditions, but, in particular, for research on

efficient blades with hydro-dynamic profile. The pilot-

station will be anchored to the bank with adjustable

cables on its length via a communicating bridge. The
scheme of industrial prototype is proposed in fig. 2. It

has a very simple construction and is destined to pro-

duce 3-10kW/h. The vertical rotor has 3 or 5 blades

with hydrodynamic profile, positioned under an enter-
ing angle

a

which is variable concerning the water

stream speed.

Innovative Aspect and Main Advantages

The efficiency of the micro hydropower plant depends

completely on the efficiency of the multi-blade vertical

axis rotor. The proposed multi-blade rotor with pintle

allows the increase of conversion efficiency (Betz coef-
ficient) up to 0,45 (the maximum theoretical value is

0,59), but the known technical solutions reach the

value of approx. 0,3. The proposed diagram of the

micro hydropower station axle ensures the following

basic advantages: utilization of hydrodynamic profiles
oriented to an entering angle which is variable con-

cerning the flowing water speed; inefficient zones from

the point of view of energy conversion are excluded by

repositioning of blades which cross these zones; and
the civil engineering expenses are minimum. All

blades participate actively in flowing water kinetic en-

ergy conversion whatever the rotor angular position.

Areas of Application

The designed micro hydropower stations aim at the satis-
faction of energy needs (for example, electrical or me-

chanical energy utilization for water pumping for irriga-

tion purposes) of decentralized consumers, especially in

rural districts, without building dams or lakes for water
accumulation. It can be used separately or in a system

integrated into other renewable energy conversion sys-

tems.

Fig.1 Pilot-station of the bi-functional micro-hydro-

power plant

Stage of Development

The designed micro hydropower station is protected by

the following patents: nr. 2981MD; 2991MD; 2992MD;

2993MD; 3104MD. Actually the pilot station of the mi-
cro hydropower station is in the final fabrication stage

and will be mounted on the Prut River in Stoienesti vil-

lage. The industrial prototype is in the designing stage.

Mechanical enterprises INCOMAŞ, Hidrotehnica and

Topaz, which have hold of fabrication technologies for
components, will produce low cost micro hydropower

stations at the demand of the decentralized consumers.

Contact Details
Technical University of Moldova

Contact persons: Ion Bostan, Valeriu Dulgheru

Address: Republic of Moldova, Chisinau, 168, Stefan cel

Mare Ave., Centre for the Elaboration of Renewable

Energy Conversion Systems (CERECS)
Tel/Fax: + (373 22) 23 78 61, + (373 22) 44 50 88

E-mail:

[e-mail]; [e-mail]

STCU Senior Specialist:
Alfreda Rosca [[e-mail]]

a. b.

Fig.2 Industrial prototype of the micro-hydro-power plant