smart grids, energy efficiency and renewable energy sources in urban areas: the “smart ...

CP EXPO Community Protection 2013 Genova, 30-10-2013

Federico Delfino

University of Genoa - ITALY

Dept. of Electrical, Naval & ICT Engineering

[email protected]

Smart Grids, Energy Efficiency and Renewable

Energy Sources in Urban Areas: the “Smart

Polygeneration Microgrid” of the University of

Genoa


Outline of the presentation

• The Savona Campus: a research & teaching facility of the

University of Genoa

• The Smart Polygeneration Microgrid (SPM) project

• The Smart Energy Building (SEB) project

• Economic & Environmental Analysis

o Reduction of annual energy operating costs

o Reduction of CO2 emissions

• Conclusions


The Savona Campus: a R&T facility of the University of Genoa

• 50,000 square meters

• courses from the Faculties of Engineering, Medicine, and Media Sciences

• laboratories, research centers and private companies (several operating in the environment &energy field)

• library, residences, canteen, café, etc…


The Smart Polygeneration Microgrid (SPM) Project

• Special project in the energy sector funded by the Italian Ministry of Education,

University and Research (amount 2.4 M€)

• SPM is a 3-phase low voltage (400 V line-to-line) “intelligent” distribution system

running inside Savona Campus and connecting:

• 2 mCHP Gas Turbine (95kWe, 170 kWth) fed by natural gas;

• 1 PV field (80 kWp);

• 3 CSP equipped with Stirling engines (3 kWe; 9 kWth);

• 1 absorption chiller (H2O/LiBr) with a storage tank;

• 1 electrical storage: NaNiCl2 batteries (100 kWh)

• 2 PEV charging stations.



SPM one-line diagram: - 400 V distribution system (ring network, 500m long)

-five switchboards



SPM planning, supervision & control system

RTU

TM 1703 ACP

planning

& management

supervision

& control

field data acquisitions &

local automation

IEC 61850

SICAM

DEMS



SPM

ICT infrastructure



Main goals:

• to build a R&D facility test-bed for both renewable and fossil energy sources

• to promote joint scientific programs among University, industrial companies and distribution network operators

Day-ahead production scheduling of dispatchable sources and storage exploiting renewables forecast and optimization techniques

• to optimize thermal & electrical energy consumptions, minimizing the CO2 emissions, annual operating costs and primary energy use of the whole University Campus


The Smart Energy Building (SEB) Project

• Special project in the energy efficiency sector funded by the Italian Ministry for

Environment (amount 3.0 M€)

• SEB is an environmentally sustainable building connected to the SPM, equipped by

renewable power plants and characterized by energy efficiency measures:

• Geothermal heat pump

• PV plant on the roof (20 kWp)

• Micro wind turbine (horizontal axis, 3 kW)

• High performance thermal insulation

materials for building applications

• Ventilated facades


SPM & SEB inside the Savona

Campus of the University of

Genoa

• SEB is an “active load” of the SPM

SEB is an energy “PROSUMER”


Storage-related research activity

• SPM OPTIMAL SCHEDULING

DEMS uses

o costs and revenues functions;

o forecast of electric and thermal energy demand;

o operative constraints (equipment ratings, maximum power ramp, etc.);

o forecast of the renewable units production by resorting to weather services and

historical records

to compute a scheduling for dispatchable sources including storage, which

minimizes the daily energy costs. The optimization process has a time-horizon of 1 day

(typical of a day-ahead energy market session), subdivided in 15 minutes time-intervals.

The optimization method is based on linear programming.

• This research line results at the storage level in an automatic production shifting

application


Storage-related research activity

Storage state of charge variation on

a typical winter day

Production from

dispatchable sources PV Production & Demands


Economic & Environmental Analysis

• Two different scenarios are considered

AS-IS

Without SPM & SEB

TO-BE

With SPM & SEB

• Electrical Energy

→ National Grid + SPM + SEB

• Thermal Energy

→ 2 boilers + SPM + SEB

• Electrical Energy

→ National Grid

• Thermal Energy

→ 2 boilers (gas,1000 kWth)


AS-IS scenario: energy consumptions and operating costs

Including also

maintenance

cost


TO BE scenario: share of electricity and heat generation

ELECTRICITY

˜ 37% delivered by

SPM and SEB

generation units

HEAT

˜ 25% delivered by

SPM and SEB

generation units


SPM / SEB energy consumption and production

Assumptions:

-winter operation for mGTs,

2000 hours at rated power

-absorption chiller turned off


Calculation of the total operating costs for the 2 scenarios

_ _T AS IS AS IS pp AS IS pp m AS ISC EEC e TEC TES C

_ _ _ _

_ _ _ _

65, 30

T TO BE el Grid pp th Boiler pp m TO BE

el SPM el SEB f f k f k

k C C

C E e E TES C

E E e M p

where:

_ _ _ _ _el Grid AS IS el EHP el SPM el SEB el SEBE EEC E E E E

_ _ _th Boiler AS IS th SPM th SEBE TEC E E

and Cm and pf being respectively the maintenance cost and the natural

gas price for the mGTs

; Mf_k = m3 natural gas used by

each mGT


Calculation of the total operating costs for the 2 scenarios


where:

ef-n = 0.465 tCO2/MWhel (the emission factor of the Italian electrical mix);

ηel_Grid =0.9 (national electrical grid efficiency);

ef-NG = 1.961·10-3 tCO2/m3 (natural gas emission factor);

Of = 0.995 (natural gas oxidation factor);

LHV=9.7·10-3 MWhpe/m3 (natural gas lower heating value).

Calculation of the CO2 emissions for the 2 scenarios

2_

_

f n f NG f

AS IS AS IS AS IS

el Grid Boiler

e e OCO EEC TEC

LHV

_

2 _ _ _

65, 30_

+f n th Boliler

TO BE el Grid f NG f f k

k C Cel Grid Boiler

e ECO E e O M

LHV


Calculation of the CO2 emissions for the 2 scenarios


Economic & Environmental Analysis

Economic and environmental benefits provided by the system SPM + SEB can be

further increased by:

• using the mGTs in trigeneration asset (resorting to the absorption chiller) in order to

cool the library of the Savona Campus (now cooled by means of an electrical heat

pump) during summer months (+ 600 working hours for the mGTs with respect to the

examined case)


Conclusions

• The “Sustainable Energy” R&D infrastructures under construction at the Savona

Campus of the University of Genoa have been described and the main research

lines that can be investigated by means of their use have been outlined

• An approach has been presented to assess the Campus operating costs, CO2

emissions and primary energy saving on a yearly time-scale

• It has been shown that the Smart Polygneration Microgrid (SPM) and the Smart

Energy Building (SEB) contribute to increase the overall energy efficiency of the

Campus, lowering its environmental impact

• It should be underlined that the revenues obtained by the improved energy

performances of the whole Campus can be then employed to financially support

research activities and to yearly upgrade the two pilot plants SPM + SEB

smart grids, energy efficiency and renewable energy sources in urban areas: the “smart ...

Technology

energy sector

seb thermal energy

renewable energy sources

energy efficiency sector

fossil energy sources

energy efficiency measures

daily energy costs

primary energy use