有几个因素会影响绿色电力成本，它们中的大多数取决于机构做出的选择。这些因素包括：
- 绿色电力产品选项（更多讨论见第4章）
- 绿色电力供应商（例如，是否有竞标）
- 可再生资源和技术类型（例如，风能、太阳能、水力、生物质）
- 绿色电力采购量
- 合同期限和条款
- 可用的绿色电力激励措施
- 发电厂或消费者的位置
图3-4说明了可再生能源和化石燃料技术的平均成本，并显示了几种清洁能源技术现在在成本上与传统能源已具有竞争力10。尽管取得了这一进展，但机构选择的产品类型会在成本和成本产生方式上产生很大差异。例如，对消费者而言，即使额外成本很低，购买非捆绑式RECs仍然要比标准电费高一些。从公用事业公司购买绿色电力通常也是如此。
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，图3-4中所示的某些具有成本竞争力的可再生能源技术使越来越多的机构更容易获得自发电和长期合同或从发电厂直接购买。
例如，虽然自发电可能需要大量的资本支出，具体取决于安装的规模，但可以通过稳定的并在某些情况下降低持续的运行成本来逐步收回成本。
长期的电力供应合同避免了前期的资本投资，并且还可以根据合同条款提供具有竞争力且可预测的电力成本。在某些州，太阳能公司将在机构所在地投资、拥有并安装一个太阳能项目，主体机构承诺在几年内购买产出。或者，信誉良好的大型能源消费者可能是公用电网提供场外绿色电力供应长期合同的理想人选。长期合同的风险在于未来电价可能会低于预期，而机构被锁定在合同中规定的较高价格上。一些合同可以指定哪一方接受较高电价的市场风险。
这些采购或产品选项可以在项目或合同的整个生命周期内节省成本。第6章，绿色电力签约，提出了将降低绿色电力采购成本的方法作为采购计划的一部分。
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.
