To examine the synergies that seem via interconnecting the taken into consideration systems, four case studies are proposed implementing 3 different variations of the version with a fixed district size (residential load) equal to 250 houses in step with house kind, and the power
transfers between metro and EVs isn’t always constrained while such connection exist. Case have a look at CS250dcL is the business-as-typical base case (without a DER systems or EV-metro connection), and corresponds to the version depicted, disposing of the connecting line (1) and the blocks grouped in (2). CS250dCL implements the unlimited connection among the EVs and the metro electric substation however with out DER (eliminating the blocks grouped in 2). In case look at CS250DcL DER is implemented but with separate metro and EV
optimization (getting rid of their electric connection), and CS250DCL correspond to the entire model enforcing DER structures and the joint optimization of EVs and the metro substation with the unlimited interconnection .Below Table shows the ate up electricity prices (calculated with (35), (37) and (45)) and DER expenses, (39) – (44). Table 47 indicates the power expenses, calculated with (36) and (46), and Below Table show synergies different device expenses (thermal electricity, (38), and EV battery expenses, (47)) and total costs (34), summing up all the expenses. For CSdcL, it could be seen how the expenses for the district and the total prices boom with the wide variety of EVs, due to the greater load of extra EVs. For the metro substation, as the systems have no longer been interconnected, the price has now not been affected.
Looking at the effects from the tables, it may be visible that:
1. The connection metro-EV brings substantial reductions to the metro gadget.
2. This may be seen at the same time as comparing CSdCL, with CSdcL, where the strength expenses (see the left columns in Table forty seven) and power costs (see the left columns in Above Table) for the metro device are considerably decrease and reduce with the quantity of EVs.
- Energy expenses fall from 12.4M€ in CSdcL to 7.5 – 6M€ in CSdCL (see Table forty six).
- Power expenses fall from 2.45M€ in CSdcL to 1.48 – 1.3M€inCSdCL (see Table forty seven).
- The average discount is round 44%, for each strength and electricity prices.
3. This reduction has been resulting from the extra storage capability provided by means of more EVs, and the metro taking benefit of it, storing greater regenerative braking strength.
4. In CSDcL, metro expenses go back to those of the bottom case (see the left columns in Table 46 and Table forty seven).
5. However, in CSDcL district electricity charges decrease considerably because of the added distributed era (ingesting less energy from the grid), and the load shifting capability.
- Energy expenses fall from 12.7 – 13.8M€ in CSdcL to 5.4 – 6.4M€ in CSdCL (see the crucial columns in Table forty six).
- Power costs fall from 1.19 – 1.86M€ in CSdcL to 1.3 – 1.68M€ inCSdCL (see the imperative columns in Table forty seven).
- Around 50% of total fee discount for each strength and energy expenses.
- The prices of DER investments in CSDcL are compensated with the ensuing operation, so the total expenses are smaller than CSdCL, and CSdcL (see right columns in Table 48).
- Total cost discount of round 7% in assessment with CSdCL.
- Total value reduction of round 16% in contrast with CSdcL.
- In CSDCL DER investment and maintenance fees growth considerably (being nearly half of the total expenses, see above Table), but almost all other costs are decrease than in preceding cases.
- Especially for the thermal and electric energy expenses for each metro and district structures.
- Metro strength costs fall from 12.4M€ in CSdcL, and CSDcL, and from 7.5 – 6M€ in CSdCL to 2.7 – 1.5M€ in CSDCL, for a mean reduction of 81% and 66%, respectively (see the left columns in Table forty six) .
- District thermal electricity prices fall from 9.7M€ in CSdcL, and CSdCL, to 0.6 – 0.5M€ in CSDCL, for a mean reduction of 94% (see the right columns in Table forty six), displaying that with the creation of the HP system the thermal electricity fees (from herbal gas) nearly disappear.
- The distinction among CSDcL and CSDCL in thermal power fees is negligible (see the proper most columns in Table 46).
- District electric electricity fees fall from 12.7 – 13.8M€ in CSdcL, and 12.7 – 13.8M€ in CSdCL, to 7.5 – 8.6M€inCSDCL, for an average reduction of 40% and 51%, respectively (see the significant columns in Table forty six).
- This discount is due to the higher strength waft from the renewable
- technology to both the district (such as the EV load) and metro loads.
- However, the district electric power prices accelerated from 5.4 – 6.4M€ inCSDcL to 7.5– 8.6M€ in CSDCL, for a mean boom of 32% (see the crucial columns in Table forty six), suggesting that once the metro connection is available, the metro system also
- takes advantage from DER structures, decreasing the gain for the district.
- Looking at the machine as a whole, the total expenses (proper columns in Above Table) deliver a clean assessment of the maximum anticipated blessings of imposing the intermediate or the whole cases.
10. Comparing the total expenses towards the base case CSdcL, it may be visible that:
- Just the storage abilities provided with the aid of the EV in CSdCL, already supply a massive benefit (around 9% in common, see proper columns in Above Table) to the overall machine, especially to the metro substation.
- The inclusion of DER structures in CSDcL affords a slightly bigger cost discount (around 16% in average, see right columns in Above Table).
- Nevertheless, by way of along with each factors in CSDCL, a fair large advantage can be achieved (around 30% in common, see proper columns in Above Table) proving the prevailing synergies of drawing near the hassle globally.
- It is also critical to observation that CSDCL total advantages (30%) are larger than the sum of CSdCL and CSDcL advantages (9% and 16%, respectively, which is 25% together), displaying the significance of the joint optimization.
- Finally, the EV penetration stage does now not have an effect on extensively the predicted advantages, i.E. The price of the EV load is quite small in assessment to other loads, and the inclusion of EVs reduces the battery charges as well.
Sensitivity evaluation and dialogue of effects
A sensitivity analysis on a number of the principle version parameters has been accomplished, to offer perception on the potential applicability of the outcomes in different contexts. The evaluation is composed in increasing or decreasing by using 20% the metro power profiles and the district and metro electricity prices.Below Table shows the total charges of the base case in CSdcL and the in CSDCL case for the different fee changes. It can be seen that the trade in relative advantages is noticeably small for all the taken into consideration parameters, with benefits ranging from 26.4% to 34.2% (approx. ±4% variant relative to
the original advantages) within the studied sensitivity range. These results advocate that other structures in a comparable setup are likely to offer comparable synergies as those reported in this examine.
It is vital to statement that a large proportion of these benefits is produced by way of “opportunistic” synergies, due to the different tariffs taken into consideration. In particular, the metro machine with
higher commercial tariffs is taking benefit of the cheaper energy coming from the EVs and the district (lower residential tariff), as proven in previous sections . Nevertheless, real synergies exist among structures, produced by means of authentic efficiency gains. This type of synergies can be more easily visible within the evaluation carried out in bankruptcy 7, wherein all the taken into consideration structures buy and promote strength directly from the market (on the same energy price).