University of Cyprus (Nicosia, Cyprus)

Table of Contents

Context

The University of Cyprus DHC was built in 1999, and so far, two expansions have been completed in 2007 and 2010. Apart from the DHC syste of the University of Cyprus (UCY), no other district heating systems exist on the island of Cyprus.

UCY experiences an accelerating development with new buildings constructed. Thus, UCY is currently in the process of designing a new Energy Center for green technologies, following the State of the Art.

The next expansion of the DHC network is foreseen for 2022 and it is planned to install

  • A 5 MWp PV plant with a 2.35 MWh capacity electric battery

  • Various heating and cooling storage systems.

The energy consumed in Cyprus mainly comes from oil- and petroleum products, while both electricity and heat (e.g., space heating, hot water etc.) emits a noticeable amount of CO2.

Sankey diagram of energy flows for heating purposes in Cyprus in 2015
Sankey diagram of energy flows for heating purposes in Cyprus in 2015

In Cyprus, the annual solar radiation potential is in the range of 1,878 kWh/m2/year. It is a relatively high radiation representing a great potential for solar power as well as solar heating applications. The data shows an intense solar radiation peak in the summertime. This peak is expected to trigger a certain need for cooling. Therefore, thermal energy storage solutions are considered great assets in Cyprus, e.g., potentially storing heat (and cooling) during the summer to deliver heat in wintertime.

Solar radiation potential in Nicosia

Area

The District Cooling schematic shows the 17 buildings receiving cooling within the UCY Campus with a total area of 91,422 m2. The buildings include 10 individual and 7 in the Social Facilities, “SFC”.

University of Cyprus – District cooling schematic

The District Heating schematic shows the 29 buildings receiving heating within the Campus with a total area of 98,520 m2. The buildings include 12 Student Residences, “SRA”.

University of Cyprus – District heating schematic

Energy demand

The UCY has three types of energy demands:

Cooling of 17 buildings

in total an area of 91,422 m2 (excluding student residences)

Heating of 29 buildings

in total an area of 98,520 m2 (including student residences)

Domestic hot water

Electricity consumption in 2017, 2018 and 2019 at University of Cyprus

Current energy system

Four oil boilers of each 1,750 kW heating power with a nominal efficiency of 88%. (This 88% is because these are non-condensing boilers, and no heat reclaim is made through the boiler exhaust either).

Eight air-cooled chillers, each nominated to 1,000 kW cooling with an ESEER = 4.12. (A European Seasonal Energy Efficiency Ratio (ESEER) of 4.12 corresponds to a Coefficient of Performance (COP) value of approx. 1.2132).

The new Energy Center plans to include:

  • Solar heating

  • Air-cooled chillers

  • Ice storage (cold storage)

  • Tri-generation (combined cooling, heating, and power generation)

  • Oil-fired boilers

Proposed technologies

Considering the previous information, the following technologies and solutions will be studied for UCY:

Solar Heating Technologies; TF- FTC

Investigation of integration of WEDISTRICT solar thermal panels (TC-FTC, Tracking Concentrator for Fixed Tilt Collector) to cover the heating load of the Campus; utilization of the high solar radiation potential in Cyprus.

PV / PV-Thermal (PVT)

Investigation of PV for electricity generation. Comparison of possible PV and PVT solutions (possibly with tracking mirrors) to investigate the possibility of increasing the electrical and thermal outputs. The WEDISTRICT PV-geothermal hybrid will also be considered.

Geothermal System

Investigation of the option of a geothermal system layout as well as the WEDISTRICT PV-geothermal hybrid solution.

Heat Pump

Investigation of the performance and operation of an absorption heat pump compared to a (conventional) compression heat pump (several WEDISTRICT thermocycle technologies are available for comparison).

Advanced Absorption chiller

Investigation of the performance and operation of the WEDISTRICT advanced absorption chiller, compared to the planned air-cooled chillers.

Renewable air-cooling unit (RACU)

Investigation of the option of integrating RACUs in the buildings to deliver cooling instead of the chiller solution(s).

Biomass boiler

Investigation of the low-emission biomass boiler as either a direct substitution of the existing (relatively old) oil-fired boilers, or simply as a back-up solution, for the coverage of peak loads. The biomass performance is to be compared to the performance of the planned oil-fired boilers, included in the Energy Center.

Energy storage

Investigation of various energy storage solutions including: ● Utilisation of an optimised water storage sized for acting as solar buffer ● Utilisation of ice (cooling) storage solution(s) ● Utilisation of an electric battery

Proposed solutions

The combined solutions, presented above were proposed to the UCY for a preliminary assessment. The symbol ‘x’ indicates optional selections for a possibly better direct comparison between the solutions.

Summary of preliminary solutions proposed for SeiMilano demo-follower.

Solution 1

The proposed solution S1 reflects the solution planned for DHC at UCY after the expansion and refurbishment in 2022. This is intended to be used as a benchmark solution. Thereby solution S1 integrates and combines the technologies of FTC, PV, Heat pumps, Energy storage, CCHP and Air-cooled chillers as well as oil- or biomass fired boilers for backup.

This solution is suitable for UCY since it includes the technologies that are being considered for the production of District Heating, (fixed tilt solar collectors, geothermal system), district cooling (Air-to-water or Air-to-air heat pumps, Ice (i.e., cold) storage and Air-cooled chillers) and power production (Photovoltaics) – all three (trigeneration; in the form of a combined cooling, heating, and power plant), which are in the scope for 29 buildings, including student residences.

Expected Impact

Investigation of the installation of the new DHC equipment / plant capacity

to cover the expected DHC and electricity demands of the new residential buildings

Investigation of the possible improvements of the WEDISTRICT solar thermal panels

compared to traditional solar heating technologies

Investigation of the possible improvements regarding PV or PV-T system layouts

Investigation of the installation of heat pump technologies

General advising on planning of energy equipment

for the expansion of the UCY Campus buildings

Solution 2

The proposed solution S2 is a variation of the planned setup using RACU and/or Advanced Absorption Chilling instead of the planned air-cooled chillers to deliver cooling. In addition, part of the heating will be covered by Geothermal heating instead of the planned Oil-fired boilers.

Note that FTC, PV, HP, Energy Storage and Trigeneration are still in this configuration.

Expected Impact

Investigation of the possible improvements related to district cooling

from RACU and/or Advanced Absorption Chillers, as opposed to Air-cooled chillers

Investigation of the impact of geothermal heating to cover peak load heating

as opposed to using Oil-fired boilers

Investigation of the possible improvements regarding PV or PV-T system layouts

in combination with the WEDISTRICT Geothermal Hybrid

General advising on planning of buildings’ energy equipment alternatives

Solution 3

The proposed solution S3 is a variation of the setup using RACU, and/or Advanced Absorption Chilling, instead of Air-cooled chillers for cooling. In addition, the option of the WEDISTRICT Low-Emission Biomass Boiler technology is investigated for the purpose of heat provision, instead of the proposed geothermal (hybrid) heating in S2. Note that FTC, PV, HP, Energy Storage and Trigeneration are still in this configuration.

Expected Impact

Investigation of the possible improvements related to district cooling

from Advanced absorption chillers as opposed to air-cooled chillers (considering results from S2)

Investigation of the impact of using biomass boilers to cover peak load heating

as opposed to geothermal heating or heating from oil-fired boilers.

General advising on planning of buildings’ energy equipment alternatives

More information on the simulation activities will be posted in the future.

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