3. Results
3.1. Biomass Resource Base in Yalova
Yalova’s total biomass potential in 2023 is estimated to be 610,498 tonnes/year; This is equivalent to approximately 55,040; tonnes of oil equivalent (toe)/year. The dominant resource for biomass is forestry residues. Yalova has a total of 330,728 tonnes of forestry residue (35,392 toe) available per year. Municiple and livestock wastes also represent some strategically relevant sources of biomass because these two materials provide opportunities to improve waste management and produce energy simultaneously. Although the quantity of agricultural residues is less than that of the other biomass sources, they may still play an important role in decentralized or blended fuel scenarios.
From a project development perspective, the composition of biomass inventories is as important as their total quantity; however, because of the fact that forestry residues increase the energy density of the feedstock basket while municipal or livestock waste provides a stable continuous supply throughout the year, this combination is ideal for developing a biomass hub within the region by reducing the amount of reliance on a single season feedstock.
3.2. Feedstock Logistics and Conversion Performance
Feedstock selection depends on both conversion performance and transport economics. The revised assessment retains the original comparative feedstock-cost assumptions but removes repetitive explanation. Chicken litter has the lowest procurement cost among the compared fuels, whereas forest-root waste is more expensive on a per-ton basis but can deliver stronger energy performance when integrated into mixed-fuel configurations.
Table 3.
Feedstock sourcing and transport-cost assumptions used in the feasibility comparison.
Table 3.
Feedstock sourcing and transport-cost assumptions used in the feasibility comparison.
| Fuel type |
Source region |
Cost (USD/t) |
Transportation cost (USD/t) |
| Corn waste |
Konya, Adana |
35 |
35 |
| Chicken litter |
East and South Marmara |
15 |
25 |
| Forest root waste |
East Marmara |
50 |
25 |
Table 4.
Comparative combustion characteristics and net electricity yield of selected reactor–fuel combinations.
Table 4.
Comparative combustion characteristics and net electricity yield of selected reactor–fuel combinations.
| Reactor type |
Fuel type |
Average calorific value (kCal/kg) |
Energy yield (MWhe/t) |
| Fluidized bed reactor |
Agricultural residues |
3,500 |
0.155 |
| Co-combustion system |
Chicken litter |
4,167 |
0.142 |
| Co-combustion with forest waste |
Mixed waste |
5,000 |
0.257 |
Co-combustion using forest waste produced the most electricity at an estimated yield of 0.257 MWhe/t; this is because of the high heat content of this type of feedstock. Agricultural residues in a fluidized bed reactor produced an estimated yield of 0.155 MWhe/t. Chicken litter co-combusted with agricultural residues estimated at 0.142 MWhe/t. Therefore, it appears that co-combustion will produce more electricity when using those forest-based feedstock blends than when solely using agricultural residues, but final technology selection will depend on ash behaviour; emissions control; moisture content; and the requirement for preparation of the fuel.
3.3. Economic Feasibility
The base-case financial assumptions and outcomes are summarized in
Table 5,
Table 6 and
Table 7. The modeled project is capital-intensive, with an upfront investment of USD 60 million. Despite the aforementioned positive feasibility indicators; NPV =
$16,380,000; IRR = 10% and Payback Period = 17 years. All of these indicate that the project has a highly conditional long-term viability as an investment given stable tariff support and guaranteed access to feedstock.
The cash flow profile for the first 5 years of operation has steadily improved to where cumulative net cash flow is projected to be approximately $16.5 million by Year 5. Although, there is still significant long payback, once operational, this project will produce stable positive cash flows based on the base assumptions. Biomass projects are very sensitive to both the cost of feedstock and the tariff rate applied, thus the sensitivity results are especially significant. The study shows that by increasing the price of electricity sold by 10%, the NPV will increase by 18%. Conversely, if the price of the fuel increases by 15%, the IRR will decrease by 1.2%. Therefore, project feasibility can be derived from two key factors; (1) revenue certainty and (2) sourcing feedstock in the most transport-efficient manner.
3.4. MATLAB Optimization Results
The MATLAB optimization provides an operational planning layer beyond the static feasibility tables. For the base-case annual plant throughput of 220,000 t/year, the optimizer converged to a solution in which agricultural residues were excluded from the optimal blend, chicken litter was utilized up to its local availability limit, and the remaining demand was satisfied by forest residues. According to the comparative specific prices for feedstocks, forest residue offers the maximum electricity yield per dollar spent on delivery, chicken litter has the lowest price, and agricultural residues have the highest delivered price of any feedstock for power generation.
The ideal distribution (total amount of feedstock needed) is 140,573 tons annually for chicken litter, 79,427 tons annually for forest debris, and none for agricultural wastes. The potential yearly energy generation in this instance is 40.37 GWh (net equivalent plant capacity of about 5.42 MW at 85% capacity factor), with an average power yield of 0.184 MWh/ton. The total annual delivered feedstock expenditure is $11.58 million, yielding a delivered feedstock price of $286.8/MWh.
The results from the optimization efforts should be interpreted as a point-in-time decision-making tool for management rather than as a definitive design recommendation. Plant operators are likely to have other criteria to consider (e.g., stabilization of the firing process, ash behavior, moisture content, contract security of supply, or minimum area activity requirement). Still, it is clear that the MATLAB optimization provides a significant improvement in the management framework for biomass projects by providing managers with a data-based method of converting relatively qualitative feasibility-level data into action-oriented operating plans.
Table 8.
Optimized annual feedstock allocation obtained from the MATLAB base-case scenario.
Table 8.
Optimized annual feedstock allocation obtained from the MATLAB base-case scenario.
| Feedstock |
Optimized amount (t/year) |
Share (%) |
Electricity contribution (MWh/year) |
| Agricultural residues |
0 |
0.0 |
0.00 |
| Chicken litter |
140,573 |
63.9 |
19,961.37 |
| Forest residues |
79,427 |
36.1 |
20,412.74 |
| Total |
220,000 |
100.0 |
40,374.11 |
3.5. Environmental and Policy Implications
There is an eco-logic to supporting biomass in Yalova beyond just producing electricity. Diverting agricultural residue, forestry/landscaping waste, municipal solid waste, and animal manure to be turned into a source of power would help reduce landfill pressure, open burning activities and reliance on fossil fuels simultaneously. The original feasibility dataset projected substantial avoided CO₂ emissions over the operating period. Although the exact magnitude depends on the fossil reference case and plant dispatch profile, the direction of impact is clear: biomass can contribute to regional carbon mitigation when feedstock sourcing is sustainable and conversion systems are properly controlled.
Policy support remains central to implementation. The Turkish incentive framework for renewable energy provides a useful enabling environment, although further analysis indicates that biomass specific improvements are still needed, particularly for smaller or regionally-integrated systems. Three policy directions emerge from the analysis of the case study: (1) Improve MSW/feedstock aggregation and logistics infrastructure; (2) Simplify permitting and grid connection processes for waste-to-energy and agricultural bioenergy projects; and (3) Create regional-based support instruments for concentrated areas of waste biomass. Reducing transaction costs and increasing investor confidence are the results of these measures.
Table 9.
Qualitative comparison of alternative biomass conversion routes relevant to future studies.
Table 9.
Qualitative comparison of alternative biomass conversion routes relevant to future studies.
| Technology |
Energy efficiency |
Capital cost |
Emission level |
| Gasification |
High |
Medium |
Low |
| Pyrolysis |
Medium |
Medium |
Low |
| Anaerobic digestion |
Low |
Low |
Very low |