3.1.3 HOMER pro model

Figure 15 shows the HOMER pro model built for current study with two electric transmission lines, i.e., DC and AC. Basically, the electricity generated from each energy source is stored in the battery based on the DC line. This is because, in comparison with AC, small-scale power generation systems can reduce losses due to electricity conversion. Electric load is used after converting it to AC by using the converter as shown in the figure.

Table 4 displays the values of all the sensitivity variables considered in current study. First values of all sensitivity variables in Table 4, makes the default case.

## 3.2 Optimum HRES solutions

This section presents the characteristics and analysis of the most optimal HRESs recommended for Deokjeokdo island on the basis of techno-economic evaluations.

HOMER simulations generated a total of 551,035 alternatives, out of which only 232,683 solutions were found to be feasible. Figure 16 shows the breakdown of all the solutions generated and it also specifies the multiple reasons for omitted

Out of the 232,683 feasible solutions, only following two HRESs were finalized as

solutions.

175

Figure 15.

(a) Converter

Leonics MTP-413F 25kW

(b) Battery

Surrette 6CS25P (kinetic)

CS6X-325P

STX 93/2000

Table 3. Selected equipment.

(c) PV panel Model Capital (\$/kW)

Model Capital

Model Capital

(d) Wind turbine [10] Model Capital (\$/ wind turbine)

(\$/kW)

DOI: http://dx.doi.org/10.5772/intechopen.85221

(\$/battery)

Replacement (\$/kW)

Evaluation of PV-Wind Hybrid Energy System for a Small Island

Replacement (\$/battery)

Replacement (\$/kW)

> Replacement (\$/wind turbine)

O&M (\$/year)

> O&M (\$/year)

O&M (\$/year)

> O&M (\$/year)

Lifetime (years)

800 800 10 10 96 80 94

Lifetime (years)

250 250 1 20 100 6 6.91

Lifetime (years)

1500 1500 30 25 88 50 17

Lifetime (years)

2,869,747 2,869,747 110,375 25 80 5 10 1500

Inverter efficiency (%)

> Initial state of charge (%)

Derating factor (%)

> Hub height (m)

Wake loss (%)

Rectifier capacity (%)

> Nominal voltage (V)

Rated capacity (kW)

> Other losses (%)

Rectifier efficiency (%)

Nominal capacity (kWh)

Efficiency (%)

> Rated capacity (kW)

the most suitable options.

HOMER pro model constructed for current study.


#### Table 3. Selected equipment.

3.1.1 Electric load

Wind Solar Hybrid Renewable Energy System

Deokjeokdo island.

Ali et al. [12].

Figure 14.

174

3.1.2 Equipment selection

3.1.3 HOMER pro model

converter as shown in the figure.

3.2 Optimum HRES solutions

Total AC electric load at Deokjeok island (a) daily load (b) monthly load.

In order to optimally design a HRES, electric load information such as peak load, daily average electricity consumption and hourly load profile are of critical importance. The maximum availability of load information enables designing a more compact HRES. In the present case, the load data were not collected from any official government source (because of unavailability of such data), but from a previous study on Deokjeokdo island [11]. The average daily load was found to be approximately 24,720 kWh with peak load of 2292 kW typically occurring during winter season and total annual electricity consumption corresponds to a value of 7.296 GWh. The electricity consumption during winter season is higher than rest of the seasons due to the extensive use of space heating equipment powered by elec-

tricity. Figure 14 shows the daily and monthly electricity consumption at

Table 3 presents all technical and economic details about the selected equipment for the study. It is to be noted that all the equipment have been selected by default by HOMER pro except wind turbine; which has been selected after a detailed analysis of wind characteristics at Deokjeokdo island by same authors in

Figure 15 shows the HOMER pro model built for current study with two electric transmission lines, i.e., DC and AC. Basically, the electricity generated from each energy source is stored in the battery based on the DC line. This is because, in comparison with AC, small-scale power generation systems can reduce losses due to electricity conversion. Electric load is used after converting it to AC by using the

Table 4 displays the values of all the sensitivity variables considered in current study. First values of all sensitivity variables in Table 4, makes the default case.

This section presents the characteristics and analysis of the most optimal HRESs recommended for Deokjeokdo island on the basis of techno-economic evaluations.

Figure 15.

HOMER pro model constructed for current study.

HOMER simulations generated a total of 551,035 alternatives, out of which only 232,683 solutions were found to be feasible. Figure 16 shows the breakdown of all the solutions generated and it also specifies the multiple reasons for omitted solutions.

Out of the 232,683 feasible solutions, only following two HRESs were finalized as the most suitable options.


Table 5 shows the basic characteristics of both of the optimized system solutions. It is to be noted that both systems have batteries as default option for storing surplus electricity. System A has the lowest overall NPC (11.3 million \$) whereas LCOE is lowest in case of system B (\$ 0.123). Table 5 also displays the values of

sensitivity variables at which optimal system solutions have been obtained. Project life of system A (15 years) is less than that of system B (25 years), which is also one

Table 6 displays the selected size of each component for both systems. Both systems consist of one wind turbine and system converter of almost 1000 kW size. PV panel size for system B (3,157 kW) is higher than system A (2,504 kW), that is why NPC of system B is higher than system A. By selecting an appropriate model of wind turbine according to the wind conditions of Deokjeokdo island, both system architectures might be different from present cases. But, a right choice of wind

Pollutant Unit Quantity (system A) Quantity (system B)

Carbon dioxide kg/year 795 700 Carbon monoxide kg/year 8.83 7.77 Unburned hydrocarbons kg/year 0 0 Particulate matter kg/year 0 0 Sulfur dioxide kg/year 0 0 Nitrogen oxides kg/year 5.52 4.86

of the reasons for low NPC of system A.

DOI: http://dx.doi.org/10.5772/intechopen.85221

Evaluation of PV-Wind Hybrid Energy System for a Small Island

Table 7. Pollutants emission.

Figure 17.

177

Daily PV power output for both systems (a) system A (b) system B.


### Table 4.

Sensitivity variables.

#### Figure 16.

Breakdown of multiple solutions obtained from HOMER simulations.


#### Table 5.

Basic information about both system solutions.


#### Table 6. Systems architecture.
