Exhibit (c)(4)

Presentation to the Board of Directors  Project Revere  Strictly Private and Confidential  Corporate and Investment Banking | Global Power  December 18, 2015

U.S. Equity Market Performance Source: FactSet. Note: Market data as of December 15, 2015.  1. Based on S&P 500 Energy Sector composed of Energy Equipment & Services and Oil, Gas & Consumable Fuels.  2. Based on Alerian MLP index.  The S&P 500 Has Been Flat YTD, While Energy and IPPs Have Continued to Fall  (December 31, 2014 to Present) 30 40 50 60 70 80 90 100 110%Dec-14 Jan-15 Feb-15 Mar-15 Apr-15 May-15 Jun-15 Jul-15 Aug-15 Sep-15 Oct-15 Nov-15 Dec-15 Relative Stock Price Performance IPPs: (58%) S&P 500: (1%) Energy: (22%)  Sector Performance: Commodity-Linked Names Have Been the Worst Market Performers  (2014 and 2015 YTD) 8.0% 18.2% 23.3% 12.9% 13.1% (1.9%) 7.5% 24.3% (10.0%) (0.9%) 6.6% 8.9% 5.1% 4.3% 2.7% (3.1%) (3.4%) (5.7%) (11.2%) (21.7%) (45.5%) (58.4%) (70) (50) (30) (10) 10 30% Consumer Discretionary Information Technology Healthcare Consumer Staples Financials Telecom Industrials Utilities Energy MLP IPPs 2014 % Change 2015YTD % Change  In 2015, Energy and IPPs have been the worst performers and have had their worst years historically  2  1  3  3. IPP index includes CPN, DYN, NRG and TLN. TLN added to the index on June 2, 2015.  1

Share P rice Performance Since: 6/2/2015 S&P 500 (3.1%) Henry Hub (35.0) WTI Crude Oil (39.1) IPP Average (59.1) TLN (67.9%) CPN (38.2) DYN (67.9) NRG (62.5)  0 20 40 60 80 100 120%Jun-15 Jul-15 Aug-15 Sep-15 Oct-15 Nov-15 Dec-15 S&P500: (3.1%) Henry Hub: (35.0%) CPN: (38.2%) NRG: (62.5%) DYN: (67.9%) TLN: (67.9%) WTI Crude Oil: (39.1%)  Key Updates to the IPP Sector  • IPP stock performance has come under pressure largely driven by the commodity sell-off  • In light of steep losses, many investors are liquidating positions and exiting the sector  • Unlike some other energy sub-sectors, the IPP sector has no looming credit crisis  • Equity analysts are more measured, and believe the sell-off may be overdone   Relative Price Performance  (June 2, 2015 to Present) Source: FactSet and SNL. Note: Market data as of December 15, 2015.  IPP decline has far exceeded the fall in gas prices  Commentary 2

Buy 38% Hold 63%  Source: FactSet and Wall Street Research. Note: Market data as of December 15, 2015.  1. Based on available analyst research reports. “Overweight” ratings are marked as “Buy” and “Neutral” ratings have been marked as “Hold.”  Talen Wall Street Research Estimates and Commentary  Talen-Specific Wall Street Research Commentary  Selected Research Estimates1  Analyst Recommendations  Current Price: $6.01  ▲ With the completion of its asset sales, Talen will have considerable liquidity and financial flexibility  ▲ Talen offers investors extensive exposure to PJM, which is the most liquid and attractive power market  ▲ MACH Gen acquisition added geographic diversity and more CCGT assets that generate solid cash flows  ▼ Significant solid fuel fleet that is highly-levered to gas prices  ▼ Concentration of cash flows from Susquehanna  ▼ Leverage metrics worsening as hedges roll off   IPP Wall Street Research Commentary “IPPs – several worries but this is getting silly.” Analyst 5 (December 6, 2015)  “Companies have all met 2015 guidance, provided 2016 guidance in line, have meaningful future cash flow locked-up with hedges / capacity revenue / retail, and still look to generate significant free cash flow even on our refreshed mark-to-market numbers.”  Analyst 5 (December 6, 2015)  “We cannot find a low enough natural gas price to justify the current valuations.”  Analyst 93 (December 7, 2015)  2. Midpoint of Company guidance based on latest investor presentation.  3. Not included in table above for lack of data.   3 EBITDA Estimates Analyst Date Rating Target Price 2015 2016 2017 2018 CAGR Analyst 1 12/08/15 Buy $11.50 $1,057 $764 $693 - (19.0%) Analyst 2 12/08/15 Buy 12.00 1,075 760 705 - (19.0) Analyst 3 11/23/15 Hold 15.00 1,070 868 777 661 (14.8) Analyst 4 11/16/15 Hold 16.00 1,052 831 734 646 (15.0) Analyst 5 11/05/15 Hold 12.00 1,090 865 755 660 (15.4) Analyst 6 12/14/15 Hold 7.00 1,088 835 675 625 (16.9) Analyst 7 11/06/15 Buy 16.00 1,025 813 791 - (12.2) Analyst 8 10/26/15 Hold 11.00 1,005 909 689 718 (10.6) Consensus $12.56 Current 6.01 EBITDA Estimates 2015 2016 2017 2018 CAGR Median Consensus $1,063 $833 $720 $646 (15.3%) Company Projections 1,075 845

TLN CPN DYN NRG TLN CPN DYN NRG TLN CPN DYN NRG Share Price $18.74 $20.13 $32.29 $24.72 $13.58 $15.41 $25.25 $19.24 $6.01 $12.44 $10.37 $9.28 Firm Value 6,115 18,480 9,966 28,097 5,452 16,853 10,093 26,506 4,157 16,038 7,819 22,628 2016 EBITDA Guidance 885 1,875 1,200 3,100 990 1,875 1,200 3,100 845 1,875 1,200 3,100 6.9x 5.5x 4.9x 9.9x 9.0x 8.6x 8.5x 8.3x 8.4x 6.5x 9.1x 8.6x 7.3x June 2, 2015 September 1, 2015 December 15, 2015 Historical FY+1 Average EV/EBITDA TLN CPN DYN NRG  IPP Valuations Have Fallen Precipitously Since June FY+1 EV/EBITDA Multiples (June 2, 2015 to Present) Source: FactSet and Company filings. Note: Market data as of December 15, 2015.  1. Historical FY+1 six-year average EV/EBITDA for CPN, DYN and NRG.  TLN CPN DYN NRG  Average  1 8.5x 7.9x  6.8x  • Since June 2, FY+1 EV/EBITDA multiples have fallen by 1.7x, well below the historical average of 8.5x  • CPN’s multiple remains elevated compared to peers due to its gas portfolio   ($ in millions, except per share data)  4

Recent IPP Valuation Trends  The changing commodity and environmental landscape has created a shift in the way some investors approach IPP valuation with differing impacts for each company. Implications for IPPs  Issue  Description  Shifting Valuation Framework   • Shift from forward EV/EBTIDA multiples and FCF Yield to DCF-based approach with no terminal value   • Coal- and nuclear-heavy  • Gas and renewables fleet   • Most of fleet economics from gas  • Significant coal   • Coal-heavy with retail focus  Leverage Position / Liquidity   • While leverage metrics in line with historical levels, investors losing appetite for leveraged names with commodity exposure  • Backwardated EBITDA    • Significant proceeds from asset sales  • Declining EBITDA  • Significant coal    • No near-term capital needs  • Flattish EBITDA    • Significant coal  • Environmental exposure    • GenOn has negative debt implications  • Complex capital structure   Supply / Demand Fundamentals   • Weakening demand growth (all markets)   • PJM-heavy  • Material exposure to ERCOT and California  • Geographically diverse post-M&A  • PJM- and ERCOT-heavy

IPP Credit Comparison Source: Investor Presentations, FactSet, SNL, Company Filings, Rating Agency Reports. Note: Market data as of December 15, 2015.  1. Reflects 2016E guidance sourced from investor presentations.  Capital Structure Overview  2016E Debt to EBITDA1   • 4.8x    • 6.5x    • 6.1x    • 6.5x   Debt / Book Capitalization   • 48%    • 79%    • 67%    • 62%   Ratings   • Corporate: Ba2 (Negative) / B+ (Stable)  • 1st lien: Baa2 / BB  • Unsecured: Ba3 / B+    • Corporate: B1 (Positive) / B+ (Stable)  • 1st lien: Ba3 / BB  • Unsecured: B3 / B    • Corporate: B2 (Positive) / B+ (Stable)  • 1st lien: Ba3 / BB  • Unsecured: B3 / B+    • Corporate: Ba3 (Stable) / BB- (Stable)  • 1st lien: Baa3 / BB+ (NRG)  • Unsecured: B1 / BB- (NRG); B3 / B- (GenOn)   Liquidity Sources ($mm)   • Undrawn Revolver: $1,300  • Unrestricted Cash: $648    • Undrawn Revolver: $1,330  • Unrestricted Cash: $659    • Undrawn Revolver: $1,425  • Unrestricted Cash: $934    • Undrawn Revolver: $1,449  • Unrestricted Cash: $2,265   Moody’s 12 – 18 month forward FFO / Debt   • 17% – 19%    • 7% – 10%    • 10% – 12%    • 8% – 11%   Cash / Market Capitalization   • 84%    • 15%    • 74%    • 76%   Cash / Share   • $5.03    • $1.82    • $7.66    • $7.09

IPP Benchmark Debt Levels Bond Bid Price (LTM)  Bond Yield to Worst (LTM, %)  Term Loan Bid Price (LTM)  Term Loan Effective Yield to Worst (LTM, %) 86.500 83.875 82.125 74.750 88.811 70.00 75.00 80.00 85.00 90.00 95.00 100.00 105.00 110.00Dec 14 Feb 15 Apr 15 Jun 15 Aug 15 Oct 15 Dec 15 CPN 5.750% due 2025 DYN 7.625% due 2024 NRG 6.250% due 2024 TESLLC 6.500% due 2025 Citi HY Index 7.854% 10.451% 9.372% 10.827% 8.263% 4.00% 5.00% 6.00% 7.00% 8.00% 9.00% 10.00% 11.00%Dec 14 Feb 15 Apr 15 Jun 15 Aug 15 Oct 15 Dec 15 CPN 5.750% due 2025 DYN 7.625% due 2024 NRG 6.250% due 2024 TESLLC 6.500% due 2025 Citi HY Index 98.500 96.250 97.000 95.875 95.00 96.00 97.00 98.00 99.00 100.00 101.00Dec 14 Feb 15 Apr 15 Jun 15 Aug 15 Oct 15 Dec 15 CPN TLB-4 CPN TLB-5 DYN TLB NRG TLB4.335% 4.177% 4.769% 4.456% 2.50% 3.00% 3.50% 4.00% 4.50% 5.00%Dec 14 Feb 15 Apr 15 Jun 15 Aug 15 Oct 15 Dec 15 CPN TLB-4 CPN TLB-5 DYN TLB NRG TLB Last 60 Days Δ CPN: (8.375) Δ DYN: (17.875) Δ NRG: (8.875) Δ TLN: (16.500) Last 60 Days Δ CPN-4: (1.375) Δ CPN-5: (2.000) Δ DYN: (2.750) Δ NRG: (1.625)  Last 60 Days  Δ CPN: 136 bps  Δ DYN: 315 bps  Δ NRG: 167 bps  Δ TLN: 302 bps Last 60 Days Δ CPN-4: 32 bps Δ CPN-5: 38 bps Δ DYN: 71 bps Δ NRG: 74 bps  In addition to the equity market sell-off of the IPPs, credit has also been impacted. Yields have widened significantly of late, and access to the debt capital markets has been challenged for Power names.  7

Firm  Overview  Financial Investors   • Apollo looking to build up its power platform and has significant dry powder earmarked for the GenCo space  • Apollo, along with Brookfield, Oaktree and Angelo Gordon, comprise Luminant’s Ad Hoc Steering Committee and will serve to drive the company’s future direction  • Luminant owns 16.7 GW of generation in ERCOT (coal, nuclear and natural gas), including recently acquired La Frontera CCGT portfolio from NextEra    • Aggressive approach to recent GenCo valuations  • Currently owns 8.1 GW of generating capacity    • Has significant experience as an owner of power generation assets; owned and operated the Texas GenCo portfolio of ~14 GW which was sold to NRG  • Blackstone’s energy franchise is an active investor in virtually every sector of the energy industry  • Currently owns 1.6 GW of generating capacity in ERCOT through its Lonestar Portfolio    • Currently owns 4 GW of generating capacity including the Cogentrix platform  • Recently acquired the 550 MW Rhode Island State Energy Center CCGT from Entergy    • Highly active in recent processes  • Recently acquired Terra-Gen Power and Wheelabrator and currently owns 2.4 GW of generating capacity    • Currently raising $15.0bn fund, interested in opportunities to deploy significant capital  • Purchased CPV and is leveraging the Company to expand its generation platform    • Currently owns approximately 11 GW of generating assets including ~9.3 GW of gas-fired plants  • Most recently acquired six CCGT generation facilities totaling ~3.5 GW from Calpine

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