有幾個因素會影響綠色電力成本，它們中的大多數取決於機構做出的選擇。這些因素包括：
- 綠色電力產品選項（更多討論見第4章）
- 綠色電力供應商（例如，是否有競標）
- 可再生資源和技術類型（例如，風能、太陽能、水力、生物質）
- 綠色電力採購量
- 合同期限和條款
- 可用的綠色電力激勵措施
- 發電廠或消費者的位置
圖3-4說明了可再生能源和化石燃料技術的平均成本，並顯示了幾種清潔能源技術現在在成本上與傳統能源已具有競爭力10。儘管取得了這一進展，但機構選擇的產品類型會在成本和成本產生方式上產生很大差異。例如，對消費者而言，即使額外成本很低，購買非捆綁式RECs仍然要比標準電費高一些。從公用事業公司購買綠色電力通常也是如此。
Figure 3-4. Levelized Cost of New Power Generation Technologies in 2016 11
（Note: Here and throughout this presentation, unless otherwise indicated, analysis assumes 60% debt at 8% interest rate and 40% equity at 12% cost for conventional and Alternative Energy generation technologies. Reflects global, illustrative costs of capital, which may be significantly higher than OECD country costs of capital. See “Unsubsidized Levelized Cost of Energy—Cost of Capital Comparison” page for additional details on cost of capital. Analysis does not reflect potential impact of recent draft rule to regulate carbon emissions under Section 111(d). See Appendix for fuel costs for each technology. + Denotes distributed generation technology. REC Prices ）
相反，圖3-4中所示的某些具有成本競爭力的可再生能源技術使越來越多的機構更容易獲得自發電和長期合同或從發電廠直接購買。
例如，雖然自發電可能需要大量的資本支出，具體取決於安裝的規模，但可以通過穩定的並在某些情況下降低持續的運行成本來逐步收回成本。
長期的電力供應合同避免了前期的資本投資，並且還可以根據合同條款提供具有競爭力且可預測的電力成本。在某些州，太陽能公司將在機構所在地投資、擁有並安裝一個太陽能項目，主體機構承諾在幾年內購買產出。或者，信譽良好的大型能源消費者可能是公用電網提供場外綠色電力供應長期合同的理想人選。長期合同的風險在於未來電價可能會低於預期，而機構被鎖定在合同中規定的較高價格上。一些合同可以指定哪一方接受較高電價的市場風險。
這些採購或產品選項可以在項目或合同的整個生命週期內節省成本。第6章，綠色電力簽約，提出了將降低綠色電力採購成本的方法作為採購計劃的一部分。
The Costs
There are several factors that can affect green power costs; most of them depend on the choices an organization makes. These factors include the following:
Green power product option (discussed more in Chapter 4)
Green power supplier (e.g., competitive bid or not)
Renewable resource and technology type (e.g., wind, solar, hydro, biomass)
Quantity of green power purchased
Duration and terms of contract
Available incentives for green power
Location of the generator or consumer
Figure 3-4 illustrates the levelized costs of renewable and fossil fuel technologies and shows that several clean energy technologies are now cost-competitive with conventional energy sources.10 Despite this progress, the product type an organization chooses can make a big difference in cost and in how that cost is incurred. For example, even if the extra cost is low, purchasing unbundled RECs still comes at a cost premium on top of the standard electricity cost to the consumer. The same is usually true for purchases of green power from a utility.
In contrast, the competitive costs for some renewable energy technologies shown in Figure 3-4 have made self-gen-eration and long-term contracts or direct purchasing from generators more accessible to an increasing number of organizations.
For example, while self-generation can require a major capital outlay that varies significantly depending on the size of the installation, that cost can be recovered over time through stable and, in some cases, lower ongoing operating costs.
Long-term contracting for electricity supply avoids the upfront capital cost and may also provide competitive and predictable electricity costs depending on the contract terms. In some states, solar companies will capitalize, own and install a solar project at an organization’s site with a commitment from the host organization to purchase the output over a period of years. Alternatively, creditworthy large energy consumers may be good candidates for long-term contracts for off-site green power supply from the utility grid. The risk with long-term contracts is that future electric-ity prices may turn out to be lower than expected, and the organization is locked in to the higher price specified in the contract. Some contracts can specify which party accepts the market risk for higher electricity prices.
These procurement or product options may allow for cost savings over the life of the project or contract. Chapter 6, Contracting for Green Power, suggests methods for minimizing green power purchase costs as part of a procurement plan.
10 Levelized cost of electricity (LCOE) is used to compare the relative cost of energy produced by different energy-generating sources, regardless of the project’s scale or operating time frame. LCOE is a calculation accounting for all of a system’s expected lifetime costs (including construction, financing, fuel, maintenance, taxes, insurance and incentives), which are then divided by the system’s lifetime expected power output (in kilowatt-hours). All cost and benefit estimates are adjusted for inflation and discounted to account for the time-value of money.
11 Lazard. (2017). Lazard’s Levelized Cost of Energy Analysis—Version 10.0. Retrieved from https://www.lazard.com/media/450337/lazard-levelized-cost-of-energy-version-110.pdf.
