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A step backward – European Member States threaten to reverse progress on Single Electricity Market

by Philip Baker Christos Kolokathis on

The European Council’s proposals on the internal energy market fundamentally weaken the framework that is needed to deliver an integrated market that will benefit European energy consumers, write Philip Baker and Christos Kolokathis from the global energy policy advisors Regulatory Assistance Project (RAP). The proposals may even legalise practices that are currently — and should…

Calming Chicken Little: An EV Grid Tale Without the Scary Ending

by Jim Lazar on

When kids hear the fairy tale Chicken Little, they learn that a confused little bird is hit on the head with an acorn and concludes the sky is falling. It then manages to convince a handful of other animals of this, and they do a whole lot of running around for absolutely no good reason…

浅谈分布式发电补偿机制的几点国际经验

by Wang Xuan on

2017年底国家发改委、国家能源局联合发布了《关于开展分布式发电市场化交易试点的通知》  (发改能源[2017]1901号),为就近利用分布式能源资源迈出了新的一步。这一通知规定了分布式发电交易模式和组织形式,并对其中关键问题,如“过网费”、相关补贴和可再生能源配额和节能减排权益等做出了具体的说明。有分析认为新出台的市场化交易政策可以大幅提高分布式发电的收益,同时降低大工业用户以及工商业用户的用电成本,从而推动分布式光伏发电在售电侧的平价上网。睿博能源智库最近就分布式发电市场化举措,也做出了评论。 分布式发电的补偿机制也是国际上关注的热点,如何设计补偿机制来更好地支持分布式发电,特别是扩大分布式发电对于所有利益相关方的价值,是一个值得探究的问题。最近,睿博能源智库和美国国家可再生能源实验室(NREL)联合发表了一篇关于并网分布式发电补偿机制入门的研究,对其中的一些关键设计要素:1)电表计量和记账安排,2)分布式发电上网电价制定,以及3)终端销售电价,进行了分析和讨论。本篇文章基于以上国际经验,对重点内容进行了总结,且将继续这一话题的进一步探讨。 分布式发电补偿机制的重要性 无论是自发自用余量上网,还是在全额上网情况下,补偿机制直接影响了分布式发电所有者的收入。从系统的角度而言,分布式发电如果自发自用可能会导致电网(以及增量配电网)公司售电量的减少,同时也可能增加或者减少电网对基础设施的投资,因此对于非分布式发电的用户来说,它的影响最终取决于分布式发电对系统带来的综合成本和收益。一个精心设计的补偿机制可以趋利避害,充分体现分布式发电对电网公司、分布式发电所有者,以及非分布式所有用户的价值。 对于分布式发电所有者来说,分布式发电在选定的补偿机制下的收益和成本是相对容易预测和计算的。然而,对于电网或者其他电力用户来说,分布式发电所能避免的和新增的成本相对更难定量化,因此如果对分布式发电过度补偿,可能会带来非分布式用户用电成本的升高;反之,如果对分布式发电补偿不够,则分布式发电的投资成本不能合理地转嫁给其他用户,而抑制分布式发电的发展。 电表计量和记账安排的形式 各国对于分布式发电在电表计量和记账安排上有多种不同的形式,这里我们认为主要可以归纳为三种,即净电表、全额上网、净记账。 净电表机制(net energy metering ),允许分布式发电用户电表在发电量大于用电量时反转,从而抵消他们的净用电量。在一个记账周期(如一个月),分布式发电用户只需要支付净用电量(即总用电量减去分布式发电量)。一些情况下,多余的分布式发电额度甚至可以“存储”,用于抵消下一个记账周期的实际用电量。在一定量记账周期结束后(如一年),一种可能是多余的分布式发电额度可能会失效,即失去价值,另一种可能是购电方以一定的价格(介于0与终端销售电价之间)对其净发电量进行补偿。 全额上网(buy all-sell all),在这一模式下,电网按照单独的上网电价对所有的分布式发电进行收购,通常通过签订长期合同来实现。不同于自发自用,这些分布式用户仍然需要以终端销售电价从电网购电来满足自己全部的用电量。事实上,分布式上网电价的设计除了固定上网电价,也可以更动态的(如分时电价)甚至是引入电力市场价格。 净记账(net billing),这种机制也允许分布式用户自发自用,并将余电上网。在这一模式下与净电表机制类似,但是净记账不允许分布式发电额度在一个记账周期内存储和抵消未来的用电量—而是将净发电量进行实时计量并按事先确定的上网电价进行补偿。和全额上网的模式一样,净记账通常有单独的两块电表分别实时计量净用电量和净发电量,并在一个记账周期后,分别核算。 这三种方式,为相关方带来了许多益处,但同时也存在一些挑战(如下表)。   中国目前对于分布式光伏主要采取的是第二种和第三种电表计量和记账方式,并对分布式光伏发电上网电价在这两种模式下分别做出了明确的规定。下一步应该讨论: 如何在不同的模式下,基于分布式光伏对电网(社会)的收益和成本,更合理地设定分布式发电上网电价,从而反映出光伏的真实价值。例如,从现有的固定分布式上网电价的基础上,结合未来电力批发市场情况(例如,不同时间地点)对分布式光伏上网电价做出调整,以最优化分布式发电的布局和发展。 如何更好地设定分布式发电的“电网费”,使得分布式发电对输配电网的成本或者分布式发电从输配电网获得的收益与之相关联,以便更准确地反映分布式发电与电网之间的关系。例如,中国最近对采取市场化交易方式的分布式发电的“过网费”进行了规定,如何细化这一收费标准来匹配分布式发电对电网的成本,以及如何确定自发自用模式下分布式用户的电网收费标准需要更进一步的探索。 在分布式发电规模不断扩大之后,应该如何制定分布式发电的并网和运行规则以满足系统安全和调度的需要。例如,并网规则是否应该要求分布式光伏发电装置使用智能逆变器,以及如何补偿分布式发电对系统提供的辅助服务等问题还有待研究。  

Time for German network operators to come clean about tariffs

by Andreas Jahn on

Network tariffs are an important part of energy costs for consumers, yet, surprisingly, the way these fees are established in Germany is completely opaque, writes Andreas Jahn, Berlin-based senior associate at global energy policy advisors Regulatory Assistance Project (RAP). According to Jahn, it is unclear how network operators and the regulator calculate costs and how…

The quiet power market transformation behind the new carbon market in China

by Max Dupuy on

In December, the Chinese government announced the launch of a national carbon emissions trading scheme (ETS), which is expected to become the largest ETS in the world. This is a major development, writes Max Dupuy, senior associate at the Regulatory Assistance Project (RAP), but its success depends on an even deeper power sector transformation that…

Environmental Permits Can Help to Implement Power Sector Reform

by Christopher James on

During my trip to China this past October and November, my tenth such during that time of year, I wore my facemask only once, on a day when the air quality index (AQI) was 260. While an AQI of 260 is unacceptable and hazardous, just five years ago during the same calendar period, I experienced…

Reflections on 2017: Key Trends Shaping the Power Sector

by Jessica Shipley on

Reflection comes naturally during the holiday season. As I come to the end of my first year at RAP, I am reflecting on many interesting power sector developments from 2017. I will focus on a handful here—trends that stood out in the past year and will continue to change the electricity industry, and how it…

What’s Next for Distributed Generation in China?

by Max Dupuy Wang Xuan on

Investment in solar photovoltaic (PV) generation is surging in China, and, although utility-scale solar continues to dominate, distributed solar is also growing rapidly. The country is estimated to have added 54 GW of solar in 2017, and distributed solar accounts for about one-third of that capacity. Now, policymakers appear to be emphasizing continued growth in…

On the Road to “Efficiency First” in the Energy Union – Are we there yet?

by Edith Bayer on

In 2015, the European Commission adopted moderating energy demand as a pillar of the Energy Union and “Efficiency First” as a guiding principle underpinning it. Last Friday, the Commission released its third State of the Energy Union. So how is Europe doing on implementing “Efficiency First”? The Commission states that it “has presented nearly all the proposals…