Thanks to recent innovations driven by European Union and national policies, lately it has been possible to see the realization of effective renewable energy technologies, for both large and small-scale use, alongside considerable cost reductions for customers. As a result, businesses and households can increasingly produce and consume, some or all, their own electricity, either instantaneously or in a deferred manner through decentralized storage, behind the connection point with the grid (i.e. the meter). In such a way, it is possible to maximize self-consumption in order to increase their efficiency of energy use and reduce their exposure to electricity prices. In the paper, the use of the so-called Nanogrid for Home Application is proposed to achieve the result of the self-consumption maximization. Moreover, a framework of exchanging energy among Prosumers (Power Cloud) is illustrated to promote the use of Nanogrids for Home Applications.

1. NanoGrids for Home Application in a Power Cloud
Framework
D. Menniti, A. Pinnarelli, N. Sorrentino, A. Burgio, G. Brusco,
V. Frascà, L. Mendicino, and M. Mercuri
Department of Mechanical, Energy and Management Engineering (DIMEG)
University of Calabria Via Bucci 42C, Arcavacata di Rende - CS, Italy

2. The paper shows the higher economic benefit a prosumer may reach when he adopts
a nanogrid in a Power Cloud framework instead of in a stand alone framework.
Summary

3. A nanogrid for home application
Nanogrids are small dc microgrids (generally not over 5 kW) which typically serve a single
building or a single home. The nanogrid interconnects generation units and plants (PV,
micro-CHP Stirling-engine, gas micro-turbines, fuel cells, etc.) and electric storage systems.
Micro-sources, storage systems and loads are connected to a common dc bus through
appropriate power converters.
The Power Electronic Interface (PEI) is a bidirectional power converter that regulates the
power flow between the nanogrid and the grid. The PEI allows the nanogrid to operate as a
single system, providing ancillary services to the grid. IEC 61850-720 communication is
available.

4. Power Cloud as a model
Power Cloud is a management and business model applicable to the Integrated
Community Energy Systems (ICESs) that is locally and collectively organized energy
systems.
Power Cloud is a feasible solution for put in practice the concept of sustainable energy
communities, community energy systems, micro-grids community, and peer-to-peer
energy.

5. Urban and rural area
A PV system on the rooftop is an easy and cost-effective way to independently fulfil a part of own electricity
demand, reduce the electric bill, generate savings, contribute to the exploitation of renewable energy
sources, and contribute to the environmental preservation by reducing the greenhouse gas emissions. Such an
opportunity is evidently reserved to those users which have ample space for installing a PV system; on the
contrary, it is denied to those users which, as an example, live in apartment building.
Local demand
Remote demand
Local demand
Remote demand

6. Power Cloud for social development
Citizens may produce energy and participate in the electricity market, selling energy to the
formers. The electricity market is accessible to all citizens that become real market
operators in aggregate form. Such a transformation would have an immediate economic
return, relying on price margins that exist between the wholesale and retail prices.
Citizens in urban area and those in rural
area are joined in a process of social
development where exploiting RESs
and self-consumption are two main
pillars.
Citizens in rural area, which have large
area, oversize their PV plants so to
generate electricity for those living in
the downtown and which cannot
install a PV plant on rooftop.

7. Members of Power Cloud
Members are:
Simple Generation Systems Power Cloud Consumers Power Cloud Prosumers
Members are managed by the aggregator, i.e.
Community Energy Provider (CEP), which is a
no-profit entity which legally represents the
community. The CEP is the power dispatcher.
The CEP interfaces the Power Cloud and the
market /system operators. The CEP ensures the
functionalities of the whole system.

8. Simulating the Power Cloud
Numerical experiment were carried out so to calculate a feasible Power Cloud. Below four
fundamental rules which have been adopted for simulating power cloud.
1. The electricity not self-consumed by prosumers is given to power cloud for free
(export price is zero);
2. The cost-free electricity provided by prosumers is sold to consumers at a discounted
price (25% less than the PE i.e. price suggested by the authority each 3 months )
3. The cost-free electricity provided by prosumers and not sold to consumers is sold to
the wholesale market (zonal price);
4. The electricity price paid to simple generation systems is 5% higher than the zonal
price;
5. The electricity cost for the prosumers is the PE.
Prosumers Consumers Simple generation
systems

9. The consumer/prosumer type
3kW contractual power
5621 kWh/year
3kWp PV plant,
1400 €/kWp
3kW-3kWh EESS, DOD_lead 50%, DOD_lithium 30%, RTE 80%, tax
deduction equal to 50% of the investment costs spread over 10 years
5kW nanogrid, …….
A consumer
3kW contractual power
5621 kWh/year
A prosumer
How much it costs????
PV plant placed in Southern Italy (PVGIS)

10. Nanogrid cost: a prototype
A 3.3kW prototype of a 3-phases nanogrid has been designed and built in the
laboratory of Electric Power Systems and Renewable Energy Sources (LASEER).
The prototype to implements the innovative business/management model of Power
Cloud. The prototype is able to move the user from “Consumer” to “Prosumer”, from
“business as usual” to “power cloud”. For the real time control, the prototype adopts
the dc bus signalling (DBS) control strategy. The DBS control strategy has been
implemented in a prioritized fashion so to maximize the use of renewables and to
maximize self-consumption.

11. The consumer/prosumer type
3kW contractual power
5621 kWh/year
3kWp PV plant,
1400 €/kWp
3kW-3kWh EESS, DOD_lead 50%, DOD_lithium 30%, RTE 80%, tax
deduction equal to 50% of the investment costs spread over 10 years
5kW nanogrid, 4300€_lead, 5000€_lithium
A consumer
3kW contractual power
5621 kWh/year
A prosumer
PV plant placed in Southern Italy (PVGIS)

12. Two alternative frameworks
Power Cloud Framework
1) Can you go into debts?
2) Are you a credit worthy customer?
3) Will your income be so high in the
next 10 years to release off tax
deduction?
Stand Alone Framework
1. Contact the Power Cloud;
2. Adhere to Power cloud;
3. Enjoy the installation of your PV, EESS,
Nanogrid;
4. Pay preferential tariff for electricity bill
and installment;
5. Do not release any Tax deduction;
6. Export your electricity at 0 €/MWh.
1. Go to Bank and ask for a loan (9 %, 20 years);
2. Complete administrative procedures;
3. Install PV, EESS, Nanogrid;
4. Pay bill and installment;
5. Release Tax deduction for 10 Years;
6. Export your electricity at 39 €/MWh.
1
2
3
No
Yes
Yes
No
No
??
Yes

13. Time interval Cost/year [€] Cost [€] Saving [€]
Business as usual 0-20 1392,67 27853,40 0,00
Lead EESS without
tax deduction
0-10 1773,60
22546,00 5307,40
10-20 481,60
Lead EESS with tax
deduction *
0-10 1348,69
18296,90 9556,50
10-20 481,60
Lithium EESS without
tax deduction
0-10
1829,9 22618,50 5234,90
10-20 431,95
Lithium EESS with
tax deduction *
0-10 1369,95
18019,00 9834,40
10-20 431,95
Stand alone framework
* tax deduction equal to 50% of the investment costs spread over 10 years.
Choice 0
Choice 1
Choice 2
Choice 3
Choice 4

14. Time interval Cost/year [€] Cost [€] Saving [€]
Bussiness as usual 0-20 1392,67 27853,40 0,00
Stand alone and Power cloud framework
For all those users which cannot chose the stand alone framework Power cloud allows them to
achieve almost equal saving. Cost/Year is obtained as sum of:
• Bussiness as usual: 1392,67 = 1138,47 + 254,20
• Stand alone: 1369,95 = 412,10 + 60,70 + 1398,50 – 460,00 – 41,35
• Power Cloud: 1323,00 = 412,10 + 60,70 + 850,20 – 0,00 – 0,00
Installment in Power Cloud reduces because 1) the price for a nanogrid reduces from 5000 € to 3000 €
due to economies of scale 2) the loan lenght reduces from 9% to 2% when Power Cloud is put in
practice by Public Administration.
(EG) (Tax) (Inst) (Deduc.) (ExP)
Lithium EESS with
deduction
0-10 1369,95
18019,00 9834,40
10-20 431,95
Lithium EESS
without deduction
0-10 1323,00
17958,20 9895,20
10-20 472,82

15. A feasible Power cloud
Gestore dei Mercati Energetici (GME): costs due to the access for the exchange
energy platform and energy trading fees; b) Terna (TSO): costs due to guarantees,
dispatching and real time power imbalances; c) Distribution System Operator (DSO):
energy transport and system charges; d) Agenzia delle Dogane e Monopoli (ADeM):
excise duty; e) Aggregator: daily operations of PC management such as the billing
system, measurement, software, personnel and general expenses.
A Power Cloud of 4037 members has revenues from the energy sale to the 1011 users and
to the whosale market; these revenues are 300 000€ and they balance the costs.
A feasible Power Cloud as 4037 members. Among members, 1011 of them have not a
nanogrid, any PV plant, any EESS; they buy electricity from Power Cloud and benefit of a
discount of 25% on electricity price. Among them, 3025 of them have a nanogrid, a PV
plant and an EESS; they buy and sell electricity inside the power cloud to members and
outside to the whosale market. It remains 1 member with an equivalent 9 MW PV plant.
Why a Power Cloud of 4037 members?
The Power Cloud is a no-profit organization. A Power Cloud of 4037 members has costs;
these costs are estimated being 300 000 € (about 75 € member/year.

16. Conclusion
The paper demonstrated the higher economic benefit a prosumer may reach when he
adopts a nanogrid in a Power Cloud framework instead of in a stand alone framework.
A Power Cloud framework also:
- allows a wider spread of electricity storage systems – so to maximize the self
consumption – preventing incentive policies from Governments.
A Power Cloud also favorites:
- the exploitation of renewables sources;
- the economic growth of less-affluent Regions;
- the participation and the involvement of citizens;
- the reinforcement of schemes of mutual support.

17. Thank you for your attention
D. Menniti, A. Pinnarelli, N. Sorrentino, A. Burgio, G. Brusco,
V. Frascà, L. Mendicino, and M. Mercuri
Department of Mechanical, Energy and Management Engineering (DIMEG)
University of Calabria Via Bucci 42C, Arcavacata di Rende - CS, Italy