SOLARGE

Dom starejših obcanov Preddvor

Preddvor, Slovenia

Pension house | 144 sqm installation

+++ photo gallery +++

 


Project summary · Technical description · Financing · Development · Downloads

Project Summary

Description

The elderly home of Preddvor is home of 190 guests, mainly pensioners and disabled people. 90 employees take care for them. There are two residential buildings, the older one built in 1680 and the newer one in 1990. The buildings are well maintained, still not thermal insulated; ventilation is natural. Since 2003 the buildings are heated by a biomass district heating plant. The boiler house is 1.5 km away. Except LG for drying and ironing, all heat demands are covered with "green heat".
Specific energy consumption for heating is 165 kWh/m2 per year. Energy demand for tap water heating is 290 MWh per year, the solar fraction of CSTS is 25 %.



 


Building

Type of building

Pension house

Number of users / dwellings, floors

190 users
(2 ×) 3 floors

Year of construction

1680 / 2000

Total effective area (heated)

4,525m2

Hot tap water consumption (measured/estimated)

4,950 m3/a

Whole energy consumption for heating purpose after CSTS implementation

290,000 kWh/a


System engineering

Year of construction of CSTS

1990 / 2000

Type of collectors

Flat plate collectors

Thermal power

100 kWtherm.

Aperture area of collectors*)

144 m2

Buffer storage

./. m3

Hot tap water storage

8.4 m3

Total capacity of boilers with energy source

not available
(district heating)

Type of hot tap water heating

Centralised

Type of heating system

Centralised


Costs

Total cost solar system

not available

Cost of the CSTS / gross area of collectors

not available 

Subsidies

0 %


Output

Output of solar heat**)

not available

Reduction of final energy***)

72,500 kWh/a

CO2-emissions avoided

29 CO2/a

Solar performance guarantee

No

*) Aperture area = light transmitting area of the front glass
**) measured, between storage and piping to taps (solar system output)
***) related to the measured output mentioned before

 

 


Mr. Peter Starc, General Manager:

"As General Manager I am proud that Elderly home Preddvor use only 'green heat' for space and tap water heating. We found out that our decisions were completely correct. Currently we working of thermal renovation of newer building and we will consider to enlarge solar system further. As there are many of elderly homes in Slovenia, our experience should be very interested for the owners."

 

 


Owner and operator

Elderly home Preddvor
Mr. Peter Starc
Potoce 2
Preddvor, Slovenia
Phone: + 386 4 2752000
Fax: + 386 4 2551110
Dom.preddvor(at)dso-preddvor.si
www.dso-preddvor.si

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Technical description

 


Description of the CSTS

Year of construction of CSTS

1990 / 2000

Thermal power

100 kWtherm.

Gross area of collectors

not available

Aperture area of collectors

144 m2 

Type of collectors

Flat plate collectors

Type of assembly

Roof top

Orientation of collectors

South (0°)

Inclination angle to horizon

40 °

Freezing protection

Drain-back

Overheating protection

Drain-back

Operation mode

Low flow

Use of CSTS for

Hot tap water heating

Buffer storage

./.

Hot tap water storage

8.4 m3: three storages in series (0.8 m3, 1.6 m3, 6.0 m3). Solar systems have separate storages, because built in different years. Integrated tube heat exchanger (third storage) for auxiliary heating with biomass for thermal shocks (few times per year, for short period) with the old boiler using heating oil.

Control of backup-system / CSTS

Separated control


Hot tap water system

Type of hot water heating

Centralised

Recirculation system

Yes

For decentralised systems:
The installation on the consumer site

./.

Size of storage for hot tap water

8.4 m3

Specification (if necessary)

./.


Space heating system

Type of heating system

Centralised

Number of boilers

1 (heat exchanger)

Total capacity (power output) of boilers

not available

Capacity of each boiler (year of construction)

not available

Energy source

District heating (biomass)

Type of boiler system

./.


Type of operation

Operator of the CSTS system

Self-operation

CSTS monitoring

No: The district heat consumption for space heating and tap water heating are measured separately, no data for CSTS. There is non observation of operating of the solar system.

Data accessible via internet

No

Scientific monitoring / follow up

No

Maintenance contract

No

Visualisation of the solar heat output

No


Yield of CSTS plant

Output of solar heat

not available

Origin of data

./.

Measuring point

./.

Reduction of final energy

72,500 kWh/a

Origin of data

The following data are available (in 2005):
Fresh water consumption: 14,835 m3
Hot water consumption: 4,950 m3
Heat for heating: 745,959 kWh
Heat for tap water
auxiliary heating: 218,130 kWh

Calculated energy consumption
for tap water heating: 290 MWh/a
Solar fraction of CSTS: 25 %
=72,500 kWh/a

Not included in energy performance:
Liquid gas for drying and ironing of towels, sheets, …: 10.716 l

Solar performance guarantee

No


Heat consumption

Whole energy consumption for heating purposes after CSTS implementation

290,000 kWh/a

Origin of data

Measured

Energy used for

Hot tap water heating

Whole energy consumption for heating purposes before CSTS implementation

not available

Total tap water consumption

14,835 m3/a

Hot tap water consumption

4,950 m3/a

Hot tap water temperature

58–60 °C

Cold water temperature

10 °C

 

 


Summary

 

The solar system was built in two steps – the larger one with 63 solar collectors in the year 1990, the smaller one with 16 solar collectors in the year 2000. The total aperture area of solar collectors is 144 m2. Each of the systems works as drain-down-back system. The smaller system has heat storage with a volume of 800 l, the volume of the heat storage in the bigger solar system is 6,000 l. Systems are connected in sequence. Tap hot water is auxiliary heated in a third heat storage (1,600 l) by an integrated tube heat exchanger using hot water from district biomass heating system.



 

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Financing and investment

Introduction

The systems were self financed. No subsidy schemes existed at that time.

 

 


Financing of the CSTS

Form of financing

Purchase

Distribution in percentage

0 %


Costs of solar materials

Total cost of solar system

not available

Detailed costs for

Collectors

not available

Elevation / mounting structure

not available

Storage / heat exchanger

not available

Backup heater

not available

Control

not available

Installation

not available

Planning / Engineering

not available

Others

not available


Operation costs of heating system

Increase of the operation cost after CSTS implementation

not available

 



Top of page Project summary · Technical description · Financing · Development · Downloads

Development & experiences

Qualitative aspects of the CSTS

The project was initiated by interest in new technologies and environmental issues.
They are very satisfied with the CSTS operating, systems works without any intervention, and there is still some place on the roof for additional solar collectors. They will enlarge the solar system in the near future, or better will add a third system on the roof of the laundry.


Summary of experiences / Notices to the project performance

Elderly home Preddvor is home of 190 guests. All heat demands for space and water heating are covered with “green heat” by biomass district heating system and CSTS. The Solar system was built in two phases, with total aperture area of 144 m2. The CSTS is used for tap water heating. The energy consumption for tap hot water heating is 290 MWh/a and solar fraction is 25 %.

There are more then 70 elderly homes in Slovenia. And there will be several new ones in the future, because Slovenians became older, therefore "Good practice case Preddvor" can play an important role in energy conservation in buildings.

 


Experiences management

Experienced problems or failures?

not available

Found solutions to these problems or failures?

./.


Financial effects / project performance

Project economically efficient?

Yes

Fiscal or other financial effects?

No

Effects on rental fees?

not available


Experiences technical staff

Experienced problems or failures?

No

Found solutions to these problems or failures?

./.

 

 


Planner and installer

STROJ d. o. o.
Mr. Franc Stroj
Dvorska vas 31 c
Begunje, Slovenia
Phone: +386 4 5333070
Fax: +386 4 5307070
info(at)stroj-si.com
www.stroj-si.com

 

 

Top of page Project summary · Technical description · Financing · Development · Downloads

Downloads

SOLARGE_goodpractice_si_preddvor.pdf

this datasheet in printable PDF-format

0.9 M

preddvor_scheme.pdf

the hydraulic scheme

513 K

Top of page Project summary · Technical description · Financing · Development · Downloads

Photo gallery









(1) old (l.) and new (r.) accomodation building
(2) old accomodation building
(3) new accomodation building
(4) new accomodation building
(5) solar collector fields (upper part: old)
(6) plat heat exchangers
(7) smaller heat storage (800 l), drain-down chamber behind
(8) large heat storage (6000 l)