System Integration of Renewables

Decarbonising while meeting growing demand

Integrating higher shares of variable renewable energy (VRE) technologies, such as wind and solar PV, in power systems is essential for decarbonising the power sector while continuing to meet growing demand for energy. Thanks to sharply falling costs and supportive policies, VRE deployment has expanded dramatically in recent years. However, the inherent variability of wind and solar PV power generation raises challenges for power systems operators and regulators.


Market and system operation


In restructured power systems, markets can be designed in a way to optimize operational efficiencies and give optimal investment signals. While the precise market structure and accompanying instruments will vary from one jurisdiction to the next, they generally fall into three market types: long, medium, and short-term markets. In addition, there are emerging markets on ancillary services and distributed energy resources.

Markets

Long-term markets

There are generally two types of long-term markets: the first for capacity (not always in place) and the second for long-term contracts for the off-take of electricity at a predefined price.

Capacity markets are typically mechanisms where a system operator procures or imposes capacity requirements (in MW) to ensure system adequacy in the future. This is often done with longer lead-periods from three to four years allowing enough time for projects to be built. They are often implemented through capacity auctions, which can enable a level-playing field for generators, demand response, and interconnections if appropriate participation guidelines are in place. The capacity does not have to actually produce electricity – it only has to be available in case of need.

The second type of long-term markets, or long-term contracts for off-take of electricity, include power purchase agreements or feed-in tariffs. The contract duration can vary between 10 and 35 years for long-lived investments such as nuclear power plants. Such agreements can be bilateral contracts between a utility and an independent power producer, or even a large demand user and an independent producer. Very often, however, they involve government intervention aimed at promoting new investment, either via an obligation or a regulated price. These long-term contracts can also be the result of procurement mechanisms, such as auctions. Ideally these contracts should be financial rather than physical, thus providing with the option to optimize dispatch closer to real-time.

Medium-term markets

Medium-term markets allow price risk to be better managed by suppliers and consumers. In well-functioning markets, most energy should be traded before the short-term markets, from a few months in advance up to three or four years.

The medium-term market may be a formal, organised spot market with future and forward standard products, or it may be informal, with variable quantities traded bilaterally over the counter by traders or retailers. In liquid European markets, roughly 90% of energy is traded on these medium-term markets.

Short-term markets

Short-term markets (day ahead and intraday) play a key role in mobilising the flexibility of the power system, and how they are designed has effects on the cost-effectiveness of integration of renewables. These markets allow all actors to re-optimize and re-balance their portfolio close to real-time with minimal VRE forecast errors. These markets are also essential for the integration of power systems over large market areas. Prices constitute the references against which other medium- and long-term prices are set, and they motivate participants both in the short and long run.

Ancillary services markets

Ancillary markets, in particular balancing markets, are applied to remove residual system imbalances in a least-cost manner. It is key that in the normal market segment there are clear balance responsibilities to market actors. It is also key that the balancing market can tap into a wide set of flexibility options (including demand response, storage, aggregation, VRE flexibility) to minimize societal costs.

Distributed energy resources and local markets

Distributed energy resources include not only distributed generation, such as roof-top PV or small-scale bioenergy, but also distributed battery storage, flexible loads and even local grid control.

Around the world, local energy markets are emerging as an alternative for system operators looking to avoid network constraints, and even for consumers to optimize their energy consumption through microgrids. This shift implies matching the pace of technology deployment with the provision of the appropriate regulatory and institutional frameworks to enable new innovative models of system operation.

Digitalisation

As with many other sectors of the economy, digitalization is reshaping the way we operate and plan power systems. Generally, digitalization can be used to:

  • Improve system operation
  • Provide predictive maintenance and asset optimization
  • Enable end-consumer solutions: metering, billing, settlements, and demand response

The emergence of a greater number of grid-connected devices and new power system needs is driving the need for the deployment of data exchange platforms. Generally, such platforms aim to reduce transaction costs and remove entry barriers for new actors.

In order to facilitate competitiveness in the power system, the design of these platforms should balance priorities of full neutrality, non-discriminatory access to data and privacy concerns. Here, pinning down the right level of access requires close coordination with industry stakeholders to determine who should access to what data at what level of detail.

To this end, having a clear governance framework is key not only to ensure the right coordination scheme between TSOs, DNOs, and market players, but also to ensure that the right equipment is installed.

Moreover, these platforms vary in their application. For example, data platforms for end-consumer solutions may only aim to optimize the process and costs of metering, billing and settlement (as in the Danish DataHub), while grid-level platforms may be used to increase visibility of the network and enable the deployment of additional flexibility resources (as envisioned in the recommendations of the UK’s Energy Data Taskforce).

The rapid emergence of new devices and business models is increasingly driving the need for device ID platforms and raises interoperability concerns, particularly when transactions take place across multiple grid levels or across power systems.

System operation

Handling uncertainty and variability

Large-scale integration of VRE generation in power systems comes with key challenges: variability and uncertainty. Power system operators have historically been able to cope with these challenges, but the complexity of the problem has been magnified by the entrance of new technologies in both supply and demand.

Variability refers to the swings in electricity generation or demand. Power systems have historically been operated to meet significant (yet predictable) swings in demand. However increasing penetration of VRE generation means that system operations are now determined by the net load, which is the system load minus the output from VRE generators.

In systems with very high shares of renewables this can lead to steep ramps when VRE rapidly changes their output due to sudden changes in weather conditions. The key driver for increased variability in the net-load is the mismatch between the system’s load profile and locally available VRE generation profile. In some cases, the electrification of new end-uses, such as transport or heating, may be seen as an opportunity to reduce net-load variability through the introduction of demand management programmes.

	Nuclear	Lignite	Hard coal	Natural Gas	Pumped storage hydro	Other
1	10.28713017	13.40259239	3.829700002	9.708905477	0.668	1.941397644
1	10.28310783	13.36221378	3.543337882	9.728142599	0.417	1.961940264
1	10.27506316	13.20691144	3.565365737	9.77246478	0.343	1.962680254
1	10.27707433	13.1955226	3.567463628	9.675197428	0.326	1.938343869
1	10.27003524	13.20380539	3.657672941	9.656140597	0.454	1.92464879
1	10.27606874	13.2928454	3.712218107	9.676098881	0.478	1.89041109
1	10.28310783	13.58999056	4.357319586	9.695755357	0.742	1.849325851
1	10.24791237	13.60966219	5.340181515	9.938406293	0.865	1.835630771
1	10.11416963	13.77324732	6.1468206	9.800371746	2.093	1.86986847
1	10.09707469	13.89852455	6.369197045	9.510980187	1.88	1.859967156
1	10.09305235	13.94718595	6.338777626	9.370535143	1.339	1.849325851
1	10.09104118	13.97306967	6.353462863	9.258071728	1.922	1.9116937
1	10.08802443	13.95443339	5.875143717	9.192584027	1.252	1.9459314
1	10.08701884	13.9461506	5.382139335	9.040141298	0.519	1.897998621
1	10.076963	13.94097386	5.537383268	9.004743915	0.63	1.9116937
1	10.07495183	13.92544362	6.066051797	9.177144929	0.783	1.887357315
1	10.07394624	13.8995599	7.028983762	9.48794107	1.092	1.894204855
1	10.06690715	13.92958502	7.5555544	9.905470234	2.531	1.891151081
1	10.06791274	13.8995599	7.640518985	10.1442056	3.717	1.907899935
1	10.07193507	14.04243806	7.408702031	10.21873962	1.757	1.891151081
1	10.06891832	14.31162879	6.11430329	9.64938326	1.097	1.914747475
1	10.07595741	14.40791624	5.461859192	9.18507059	0.806	1.95277894
1	10.06187923	14.33647716	4.919554371	9.236871271	0.83	1.942877625
1	10.05685131	14.09213481	4.437039444	9.044755009	0.599	1.919281231
2	10.15338743	14.15529109	4.094034267	9.148956016	0.523	1.864500912
2	10.1352869	13.62312172	3.81396582	9.101078848	0.314	1.895684836
2	10.09506352	12.99155885	3.764665381	9.11217508	0.273	1.878195991
2	10.0116	12.55774764	3.856972585	9.166688067	0.217	1.875142217
2	10.22277276	14.13769016	4.187390416	9.280958362	0.397	1.857653372
2	10.26299614	15.32212938	5.385286171	9.467650012	0.476	1.861447137
2	10.21975601	15.87189968	7.953104743	9.996305893	1.071	1.824155663
2	10.22880627	16.26222624	9.214986173	10.08790163	1.448	1.840164527
2	10.23685094	16.38232672	10.05204468	9.983759391	1.616	1.829523222
2	10.25595705	16.43409417	10.58910477	10.09374559	1.464	1.815828142
2	10.25696264	16.22495368	10.68246092	10.37238958	0.781	1.871348452
2	10.24389004	15.93816202	10.74854449	10.26517049	0.564	1.878935982
2	10.23886211	16.2063174	10.31218316	10.11387225	1.132	1.783070424
2	10.22780068	16.19389321	11.84679042	10.32516686	1.266	1.862187128
2	10.21774484	16.73848677	13.0981824	10.5888618	1.747	1.899478602
2	10.21774484	16.8109612	14.24258193	10.78387463	2.623	1.895684836
2	10.20366665	16.60699745	15.30516372	11.08079551	2.033	1.936770076
2	10.19361081	16.54694721	15.68802882	11.38724482	3.962	1.977855315
2	10.19361081	16.57697233	15.99536985	11.29739719	3.588	1.916227456
2	10.19361081	16.56972489	16.23138259	11.19295712	2.3	1.875142217
2	10.17953262	16.54694721	16.35410921	10.47176165	1.357	1.885043531
2	10.15841535	16.42477603	16.37613707	10.39614589	0.53	1.888837297
2	10.1352869	16.39578626	15.00096952	10.11224963	0.366	1.885043531
2	10.21171133	16.37507928	12.95972159	10.00238098	0.45	1.912433691
3	10.17852704	16.36886719	12.73524725	10.24701908	0.268	1.932976311
3	10.18254938	16.38439742	12.12476098	10.19310971	0.217	1.94667139
3	10.18456055	16.38750347	12.46986404	10.30834421	0.19	1.94667139
3	10.19159964	16.37818533	12.29259226	10.58850121	0.31	1.929922536
3	10.18154379	16.34194811	13.52929899	10.72568514	0.222	1.919281231
3	10.19763315	16.35023091	14.88034079	11.14990095	0.417	1.878195991
3	10.25495147	16.35333695	16.92893134	12.61732215	1.13	1.881989757
3	10.2660129	16.38025603	18.08277139	13.21399774	3.329	1.875142217
3	10.285119	16.45480115	18.28416892	12.88185579	4.762	1.881989757
3	10.29115251	16.41131649	18.62507621	12.55640843	2.907	1.865240902
3	10.28914134	16.43202347	18.81073956	12.36591479	1.771	1.896424827
3	10.29115251	16.44134161	19.04150757	12.31875878	1.452	1.895684836
3	10.27506316	16.4579072	18.96598349	12.17590721	0.836	1.905586151
3	10.28210225	16.83063283	18.69430661	11.90184118	0.974	1.926128771
3	10.28310783	17.02941983	19.01947971	11.9776412	0.9	1.916227456
3	10.27104082	16.99628866	19.13381477	12.23983107	0.987	1.905586151
3	10.26500731	17.07393983	19.13066794	12.2584058	2.765	1.923074996
3	10.26299614	17.0542682	19.18940888	12.68310371	4.83	2.043746002
3	10.26802407	17.05944495	19.12647215	12.42097659	4.547	2.074189936
3	10.23483978	16.86376399	18.5212306	12.38287485	2.998	2.007840696
3	10.21271691	16.64116397	17.59501173	12.03017496	1.117	1.919281231
3	10.20668341	16.60906815	15.72998664	11.57255291	0.728	1.936030085
3	10.19763315	16.37093788	13.10237818	11.01248193	0.378	1.916227456
3	10.18456055	16.62770443	10.54924484	10.16483422	0.374	1.885043531
4	10.2006499	16.99939471	9.048203839	9.583958305	0.206	1.878195991
4	10.20567782	17.06462169	8.017090418	9.047467315	0.176	1.891891071
4	10.11316404	17.07497518	7.707651497	8.968175049	0.188	1.881989757
4	9.97841571	17.09257612	7.201010823	9.039451915	0.211	1.878195991
4	9.940203496	17.07083379	6.724789568	8.997481458	0.207	1.905586151
4	9.961320772	17.09154077	6.850663027	9.160295284	0.14	1.891891071
4	9.952270511	17.15883845	7.561848073	9.08009362	0.245	1.850805832
4	10.01059442	17.08843472	8.043314055	9.168193138	0.425	1.820361898
4	10.28813576	17.13502542	8.305550429	9.042944157	1.256	1.818048114
4	10.32333122	17.12053054	8.840512631	8.841173989	1.57	1.839330724
4	10.31428096	17.05530355	8.798554812	8.709112871	0.889	1.853025804
4	10.30120836	17.01596029	8.363242431	8.458861918	0.632	1.846178264
4	10.27003524	17.01906634	8.013943581	8.323002777	0.658	1.832483184
4	10.25394588	16.96315749	7.606952729	8.213012604	0.365	1.877362188
4	10.26199056	16.96833424	7.033179544	8.203605707	0.697	1.873568423
4	10.22780068	17.10292961	7.58807171	8.360990948	0.609	1.902532376
4	10.24187887	17.13916682	7.92583216	8.536649112	0.594	1.919281231
4	10.22176718	16.93416772	8.64750666	8.960147732	1.665	1.891151081
4	10.15841535	16.08311087	8.471283817	8.99608996	0.902	1.897998621
4	10.13428132	15.6037443	6.631433419	9.161075219	0.657	1.884303541
4	10.17551029	15.64929965	5.660109891	9.083770124	0.47	1.877456001
4	10.17551029	16.41959929	5.15976289	9.096979017	0.537	1.866814696
4	10.14433716	16.84305701	5.128294525	8.870974415	0.355	1.850065841
4	10.1352869	16.86894074	4.808366149	8.944179679	0.127	1.92538878
5	10.17249353	15.02394888	4.626898578	9.014551119	0.207	1.93223632
5	10.11919755	14.18428086	4.354172749	9.196660839	0.375	1.92538878
5	10.13729807	15.44015916	4.409766861	9.217344258	0.384	1.92538878
5	10.09808027	16.04687366	4.315361766	9.259495006	0.196	1.93908386
5	10.01964468	16.79025422	4.328998058	9.307313401	0.1	1.897998621
5	9.923108558	17.12156589	4.324802276	9.271433919	0.166	1.850065841
5	9.923108558	17.12156589	4.324802276	9.338548208	0.067	1.473451147
5	10.13830366	17.17229799	4.576549194	9.22470124	0.425	1.840164527
5	10.11416963	18.40229256	4.378298496	9.042771811	0.611	1.823415672
5	10.20567782	18.83092703	4.685639526	8.914689007	0.903	1.813514358
5	10.26500731	18.97587589	5.735633966	8.85335991	1.528	1.792971738
5	10.27506316	18.98830008	7.102409946	8.746865951	1.59	1.796025513
5	10.27807991	18.91789635	7.411848867	8.618724374	0.878	1.812774367
5	10.29316368	18.91996704	7.172689294	8.518321389	0.553	1.826469447
5	10.3052307	18.95309821	6.972340705	8.50529676	0.61	1.819621907
5	10.31729771	18.97069914	7.086675764	8.550943722	0.483	1.809720593
5	10.31327537	19.02557264	7.761147717	8.817535227	0.688	1.826469447
5	10.2981916	18.961381	8.479675381	9.085753322	1.586	1.884303541
5	10.21673925	18.74706377	8.251005263	9.34456452	0.831	1.859967156
5	9.920091804	18.77294749	7.879678558	9.21148043	0.994	1.812034377
5	9.390148735	18.91996704	7.793665027	9.335820012	0.526	1.799079287
5	9.023110366	18.93653263	7.404506249	9.307419029	0.57	1.812774367
5	9.019088028	18.90340146	7.40660414	9.396784555	0.748	1.799079287
5	8.998976336	18.80504331	6.384931228	9.275882414	0.343	1.819621907
6	8.9426636	18.55552421	5.328643114	9.309288654	0.159	1.888097306
6	8.957747369	18.59900886	5.019204193	9.423860758	0.283	1.901792386
6	8.988920491	18.70047306	4.804170367	9.451477833	0.284	1.871348452
6	9.044227642	18.70461446	4.916407535	9.81080956	0.319	1.847012067
6	8.978864645	18.72532144	6.394371737	10.14758824	0.376	1.853859607
6	9.056294657	18.76155865	10.38770724	11.08689046	0.464	1.867554686
6	9.064339333	18.69633167	13.83454213	12.37955495	1.915	1.816568132
6	9.068361672	18.70875585	15.73837821	13.18806603	3.251	1.833316987
6	9.067356087	18.99968892	16.70550595	13.29461479	3.103	1.833316987
6	9.074395179	19.17983964	16.9509592	13.43541644	2.41	1.836370762
6	9.073389595	19.14567312	17.01704276	13.44705354	2.662	1.822675682
6	9.078417518	19.1177187	17.24990866	13.45947456	2.548	1.815828142
6	9.078417518	19.12703684	17.53731973	13.34647027	1.729	1.828783231
6	9.075400764	18.93653263	17.62123537	13.35623775	1.718	1.859227165
6	9.078417518	18.83092703	17.74291305	13.43040721	1.965	1.842478311
6	9.076406348	18.81953819	17.96738738	13.44373365	2.35	1.859227165
6	9.077411933	19.04731497	18.04920513	13.41328275	3.238	1.842478311
6	9.077411933	19.03799683	18.20549801	13.69476851	4.921	1.86986847
6	9.073389595	19.04938567	18.61668464	13.77581286	4.701	1.90410617
6	9.071378425	19.05456241	18.82018007	13.73288217	3.415	1.88356355
6	9.058305826	18.96448705	18.77402647	13.43583977	1.833	1.91780125
6	9.067356087	18.62075119	18.5096922	12.99413892	1.026	1.92464879
6	9.060316995	18.6103977	17.03487484	12.58801574	0.556	1.91780125
6	9.03718855	18.62178654	15.03663367	11.55181072	0.24	1.91780125
7	9.047244396	18.49029722	12.91042115	11.26062023	0.136	1.914007484
7	9.074395179	18.47787304	11.36427549	11.24427967	0.128	1.907159945
7	9.081434271	18.54620607	11.29924087	11.44942454	0.201	1.892724874
7	9.082439856	18.55138281	11.56357514	11.35909481	0.08	1.920115034
7	9.079423102	18.41782279	12.28524964	11.43627839	0.094	1.899572414
7	9.073389595	18.36812604	13.97090505	11.86772967	0.147	1.88282356
7	9.071378425	18.53585258	16.84816254	13.0106677	1.281	1.858487175
7	9.059311411	18.48926187	18.73521549	13.49614987	2.25	1.811294386
7	9.058305826	18.68183678	18.81283745	13.48776594	2.543	1.808240611
7	9.052272319	18.68287213	18.12997393	13.26904763	1.623	1.845532086
7	9.060316995	18.69736702	18.30934361	13.29123612	1.347	1.845532086
7	9.06132258	18.66423585	18.89885098	12.93166136	1.781	1.774002912
7	9.056294657	18.66216515	19.11283586	12.45981141	1.634	1.775482893
7	9.066350503	18.7139326	19.06248648	12.40595684	2.782	1.761047823
7	9.073389595	18.58865537	18.92087884	12.74509122	2.951	1.808980602
7	9.07238401	18.70668516	19.03206706	12.69841732	2.756	1.781590442
7	9.064339333	18.69322562	18.78661381	12.91713166	3.525	1.846272076
7	9.062328164	18.39193907	18.75934123	13.33936427	4.983	1.886711137
7	9.068361672	18.13931392	18.80025011	13.27424112	4.425	1.895778649
7	9.059311411	18.14138462	18.79290749	13.34654493	2.719	1.839424536
7	9.063333749	18.11653625	18.72262814	13.08170551	1.54	1.846272076
7	9.058305826	18.1134302	18.04710724	12.89676594	0.648	1.839424536
7	9.06132258	17.82870923	16.07089393	12.42020857	0.258	1.849325851
7	9.054283488	17.89083017	12.65657634	11.72222854	0.184	1.92464879
8	9.059311411	17.90221901	11.39889069	11.45841208	0.173	1.945191409
8	9.067356087	17.99436507	10.7810618	10.79009904	0.218	1.952038949
8	9.069367256	18.03060228	10.80833438	10.80951645	0.145	1.942137635
8	9.067356087	17.98401158	10.69609721	11.02448756	0.092	1.952038949
8	9.069367256	17.91567855	11.62126714	11.17795327	0.166	1.921595015
8	9.07238401	17.65373526	13.63524249	11.96825417	0.142	1.89725863
8	9.066350503	17.69721991	16.56704515	13.02761585	1.328	1.856173391
8	9.066350503	17.81939109	17.91808694	13.49717681	3.503	1.815088151
8	9.055289072	17.80800225	17.98207262	14.08094532	4.265	1.968798313
8	9.066350503	18.0161074	18.5212306	14.19859031	3.536	2.180519684
8	9.06132258	18.04716786	18.73311759	14.28897881	2.501	2.188941017
8	9.067356087	17.9105018	18.78451592	14.28385203	3.223	2.175985928
8	9.069367256	17.86908784	18.81493534	14.23096564	2.476	2.154703318
8	9.067356087	17.7096441	18.83591425	13.98276857	2.542	2.127313158
8	9.069367256	17.75934085	18.43102129	13.94875871	2.607	2.179133515
8	9.06132258	17.46116035	18.67018086	14.16276563	3.74	2.643953443
8	9.060316995	17.27790358	18.68591505	14.28294661	3.608	3.095818281
8	9.054283488	17.82456784	18.86633367	14.41663432	4.229	2.792660786
8	9.029143873	18.10100601	18.88731258	14.36423399	3.596	2.178852078
8	9.049255565	18.08754647	18.73206865	14.21559326	4.071	2.022275767
8	9.053277903	18.02231949	18.64710406	13.81200209	2.173	1.91095371
8	9.049255565	17.90946645	18.4058466	12.9727383	1.162	1.89041109
8	9.051266734	17.87322924	17.71773836	12.51994122	0.624	1.853119616
8	9.053277903	17.72828038	16.25970412	11.82992178	0.256	1.877456001
9	9.059311411	17.63924037	15.30726161	11.51949417	0.255	1.921595015
9	9.055289072	17.7055027	15.0188016	11.72499961	0.165	1.955832714
9	9.060316995	17.79350737	14.85831294	11.66741374	0.206	1.948985174
9	9.057300241	17.97262274	15.32719157	11.81322065	0.197	1.948985174
9	9.06132258	18.06373345	15.64921784	11.92061606	0.17	1.955832714
9	9.065344918	18.06787484	16.48312951	12.64319906	0.367	1.866814696
9	9.046238811	17.76969434	17.4974598	13.21937153	1.03	1.828783231
9	9.055289072	17.78211853	18.50339853	13.9292317	3.251	1.828783231
9	8.910484894	17.61749804	18.50549642	14.27668329	3.492	1.86986847
9	8.773725392	17.69307852	18.40269976	14.3195552	2.83	1.873662236
9	8.7797589	17.64648781	18.35759511	14.24357488	3.096	1.859967156
9	8.77774773	17.65787665	18.14361023	14.0827522	3.369	1.846272076
9	8.774730977	17.64545246	18.1383655	13.89823199	1.588	1.86986847
9	8.772719808	17.70032596	18.09640768	13.79113838	1.45	1.928442555
9	8.767691885	17.39075662	18.17717648	13.90540868	2.076	1.839424536
9	8.762663962	17.24684311	18.24011321	13.54468942	1.656	1.887357315
9	8.764675131	17.23648962	18.07437982	13.72650131	1.636	1.90410617
9	8.761658377	17.32656498	17.91389116	13.80568	2.914	1.948985174
9	8.751602532	17.41456964	17.53312395	13.81780318	2.855	1.948985174
9	8.746574609	17.44873616	17.07683266	13.68182649	1.041	1.87671601
9	8.734507594	17.35762545	14.81845301	12.87126549	0.357	1.935290095
9	8.726462917	17.33484777	12.00413224	12.20904342	0.555	1.894204855
9	8.726462917	17.57815478	9.551697677	11.21987289	0.46	1.884303541
9	8.728474086	17.5067157	6.48458105	10.32567279	0.375	1.93223632
10	8.722440579	16.952804	5.2038186	10.05805832	0.24	1.91854124
10	8.819982282	16.90103656	5.093679323	9.909174546	0.229	1.9459314
10	8.809926437	16.98800587	4.854519751	9.863284549	0.193	1.93908386
10	8.835066051	17.00457145	4.784240402	9.863766648	0.214	1.93223632
10	8.831043713	16.74987561	4.866058151	9.885716076	0.302	1.92538878
10	8.845121897	16.93934447	5.717801893	9.974779792	0.457	1.877456001
10	8.840093974	16.952804	7.676183132	10.69223601	1.849	1.847012067
10	8.840093974	16.99007657	9.035616493	11.38225545	3.311	1.802873053
10	8.83707722	16.94762726	8.900302525	11.47210307	3.318	1.826469447
10	8.833054882	16.86894074	8.535269492	11.42886661	3.361	1.819621907
10	8.840093974	15.96715179	8.533171601	11.34980943	2.595	1.779276658
10	8.839088389	15.47225498	8.167089624	11.33575786	1.806	1.762527804
10	8.839088389	15.32212938	7.497862398	11.13356834	0.861	1.755680264
10	8.834060466	15.32937682	6.170946347	10.96164942	1.062	1.755680264
10	8.835066051	15.3014224	5.654865163	10.99909672	1.035	1.796765503
10	8.841099558	15.28175077	5.56255796	10.80939096	0.719	1.786124198
10	8.846127481	14.91937863	5.515355412	10.85045599	0.849	1.806666818
10	8.843110728	14.77132373	5.74402553	10.99107735	1.401	1.813514358
10	8.845121897	14.91730793	5.687382474	11.00295749	0.981	1.831003203
10	8.835066051	14.71852093	5.05486834	10.8577542	1.16	1.824155663
10	8.830038128	14.93180282	4.550325557	10.41858536	0.908	1.824155663
10	8.794842668	14.5000623	4.240886636	10.12341655	0.631	1.817308123
10	8.786797992	13.40673379	3.967111862	9.584750158	0.583	1.872088442
10	8.740541101	11.83300336	3.56012101	9.224689323	0.427	1.872088442
11	8.691267457	10.26030827	3.425855986	9.239646322	0.232	1.85145201
11	8.574619647	10.14331384	3.188794305	9.191224309	0.174	1.808052987
11	8.582664323	10.51396877	3.026207753	9.131467002	0.217	1.763173982
11	8.20355894	10.97987581	2.927606876	9.080332683	0.24	1.753272667
11	8.132162435	11.85267499	3.007326734	9.329254884	0.203	1.708393663
11	8.180430495	12.50805088	3.121661793	9.190142565	0.255	1.684797269
11	8.170374649	13.83226221	3.235996852	9.165539605	0.245	1.633810715
11	8.194508679	15.0053126	3.515016354	9.241457174	0.334	1.613268095
11	8.245793492	15.18960471	3.636694031	9.141779325	1	1.59577925
11	8.369480394	15.8511927	3.829700002	9.307724811	1.138	1.62316941
11	8.399647931	16.12141878	3.594736211	9.450576379	1.412	1.636864489
11	8.420765207	16.25808485	3.772008	9.544222027	0.881	1.643712029
11	8.427804299	16.53038163	3.809770038	9.399257797	0.566	1.653613344
11	8.432832222	16.37507928	3.799280583	9.159918812	1.196	1.663514658
11	8.450932744	16.36576114	4.104523722	9.162932927	1.197	1.690904818
11	8.421770792	16.50553325	4.528297702	9.39985347	2.123	1.667308424
11	8.411714946	16.67947188	5.367454098	9.533603922	2.184	1.684057278
11	8.297078305	17.07186914	5.961157248	9.764315945	2.723	1.731990057
11	8.300095059	17.81835574	6.033534487	9.829262773	2.374	1.741891372
11	8.278977783	17.88047668	5.115707179	9.652401347	2.237	1.758640226
11	8.268921937	17.75209341	4.218858781	9.101796039	1.107	1.775389081
11	8.272944275	17.63820502	3.864315203	9.035708693	0.876	1.77464909
11	8.211603616	17.48393803	3.448932787	8.790345452	0.533	1.736617625
11	8.253838168	16.69086072	3.012571461	8.722627545	0.4	1.726716311
12	8.269927521	16.35126625	2.960124187	8.714486655	0.359	1.78149663
12	8.278977783	16.9569454	2.812222872	8.687230161	0.405	1.77464909
12	8.27394986	16.57490163	3.029354589	8.672818007	0.185	1.740411391
12	8.324229088	16.53452302	3.141591757	8.810303736	0.174	1.733563851
12	8.381547409	16.87825888	3.156276994	8.786182875	0.472	1.740411391
12	8.361435718	17.11017705	3.209773215	8.676435738	0.278	1.726716311
12	8.573614062	17.79764876	3.093340265	8.736918182	0.289	1.753460292
12	8.794842668	18.166233	3.311520928	8.943207535	0.522	1.766415382
12	8.904451387	17.79764876	3.967111862	9.09136617	0.617	1.763361607
12	8.981881399	17.85873435	5.09682616	9.255504775	0.973	1.794545532
12	8.981881399	17.99332972	6.201365766	9.348186224	2.278	1.801393072
12	8.985903737	18.08651113	7.473736651	9.510694268	2.595	1.753460292
12	8.965792045	18.09582927	7.674085241	9.439056821	2.555	1.787697992
12	8.946685939	18.27908603	7.773735063	9.354273226	0.978	1.787697992
12	8.969814384	18.36812604	7.507302907	9.259000989	0.744	1.811294386
12	8.963780876	18.47269629	7.754854044	9.367482118	1.1	1.808240611
12	8.971825553	18.55241816	8.010796745	9.619539951	1.207	1.835630771
12	8.958752953	18.44370652	8.651702442	9.816120599	2.801	1.824989466
12	9.009032182	18.50065071	8.675828189	9.873467409	3.919	1.821935691
12	9.028138289	18.48926187	8.526877928	9.871115685	2.787	1.828783231
12	9.034171796	18.48822652	8.309746211	9.770234574	0.99	1.801393072
12	9.029143873	18.50479211	7.261849661	9.567504179	0.7	1.879769785
12	9.027132704	18.47373164	6.738425859	9.188696267	0.714	1.842478311
12	8.980875814	18.48719118	4.840883459	9.067312026	0.484	1.856173391
13	8.9426636	18.47994373	4.175852015	9.052719581	0.114	1.86986847
13	9.00199309	18.43231768	4.008020736	9.108498575	0.199	1.86986847
13	9.017076859	18.37330279	3.990188663	9.095956045	0.185	1.849325851
13	9.036182965	18.46130745	4.193684089	9.145945874	0.204	1.845532086
13	9.032160627	18.5172163	5.480740211	9.353501235	0.152	1.849325851
13	9.04824998	18.52756979	8.19121537	9.841092085	0.302	1.849325851
13	9.034171796	18.46337815	12.30832644	10.87567051	1.39	1.811294386
13	9.044227642	18.46855489	15.35865994	12.00208771	1.61	1.780850452
13	9.027132704	18.47890838	16.99396596	12.51626869	1.833	1.753460292
13	9.046238811	18.44577722	16.89851192	12.5717419	1.551	1.736711438
13	9.056294657	18.39711582	17.08837106	12.53730872	1.228	1.96036647
13	9.055289072	18.39918651	17.23941921	12.25377304	0.779	1.775482893
13	9.011043351	18.23456603	16.8817288	12.0374144	0.366	1.796025513
13	9.045233227	18.28426278	17.13452466	12.0857149	0.473	1.806666818
13	9.02612712	18.28426278	17.3222859	11.94352572	0.472	1.830263212
13	9.030149458	18.26873254	17.48697035	12.36852544	0.942	1.822675682
13	8.994953998	18.2635558	17.66843792	12.45867884	1.902	1.859227165
13	9.029143873	18.32671209	17.6149417	12.70181585	3.077	1.914007484
13	9.038194135	18.33603023	17.57193493	12.81409897	2.548	1.921595015
13	9.042216473	18.33395953	17.58766911	13.03233121	2.256	1.931496329
13	9.040205304	18.30393441	17.59815857	12.8524517	1.973	1.856173391
13	9.041210888	18.30911115	17.2069019	12.35497185	1.135	1.808240611
13	9.050261149	18.34948976	16.32054296	11.80189727	1.022	1.777796677
13	9.046238811	18.35259581	13.09923134	10.88725679	0.733	1.821935691
14	9.000987505	18.13620788	12.06182425	10.94809981	0.284	1.801393072
14	8.976853476	18.12792508	11.31917084	10.9192755	0.288	1.774002912
14	8.875289434	18.15484416	10.98560617	10.86301441	0.257	1.760307832
14	8.819982282	18.0626981	10.98770406	10.80801932	0.222	1.753460292
14	8.927579832	18.11032415	10.57022375	11.08522099	0.265	1.757254058
14	8.81294319	18.10100601	11.30553454	11.41464269	0.249	1.764101597
14	8.773725392	18.1072181	13.91950672	11.8683452	0.91	1.777796677
14	8.7797589	18.18176323	15.9250905	12.27995574	2.063	1.743558978
14	8.764675131	18.19004602	16.2869767	12.25052781	1.843	1.770949137
14	8.772719808	18.05752135	15.03034	11.7739077	0.449	1.784644217
14	8.802887345	18.15380881	13.61636147	11.69497204	0.63	1.792231748
14	8.88534528	18.18279858	13.18104909	11.54029911	0.37	1.795285522
14	8.949702692	18.19522277	12.66496791	11.27352731	0.347	1.859967156
14	8.948697108	18.17969253	12.817065	11.22377655	0.686	1.934550104
14	8.842105143	18.00678925	13.75377333	11.31971514	0.536	1.87671601
14	8.877300603	17.98711762	15.52124649	11.5726784	0.484	1.89041109
14	9.055289072	18.14241997	16.35830499	11.99966927	1.21	1.842478311
14	9.054283488	18.20764695	16.46949322	12.14746732	2.271	1.897540067
14	9.045233227	18.43335303	16.08767706	12.21416225	1.335	1.98600572
14	9.047244396	18.52756979	16.48942318	12.17774587	1.094	1.90808756
14	9.047244396	18.71496795	16.30690666	12.07457578	0.783	1.89041109
14	9.050261149	18.75431121	15.41215616	11.80250089	0.941	1.901052395
14	9.054283488	18.61350375	14.14398105	11.36809427	1.122	1.859967156
14	9.052272319	18.77915958	12.05553057	10.40780683	0.586	1.879769785
15	9.034171796	18.24388417	11.80378365	10.85186338	0.202	1.958334123
15	8.989926075	18.18176323	11.31077927	11.1241813	0.173	1.964441673
15	9.002998675	18.16519765	11.56777092	11.11778852	0.135	1.948432809
15	9.009032182	17.98815297	11.37266706	11.30339445	0.421	1.930943964
15	8.961769707	17.59575571	12.26322178	11.60737051	0.108	1.948432809
15	9.006015428	17.0097482	13.66461296	12.49397457	0.631	1.983410499
15	9.00199309	16.63909327	15.472995	13.62443282	1.791	1.885971147
15	9.055289072	16.18871647	16.83137941	14.1919823	4.872	1.937145326
15	9.059311411	16.79646631	17.12823099	14.44264466	4.655	1.83128464
15	9.060316995	16.67740118	17.39885892	14.57566204	3.357	1.842665936
15	9.06132258	16.60285605	17.58347333	14.25395393	2.86	1.856361016
15	9.062328164	16.59871466	17.68941683	14.04953022	2.872	1.863208556
15	9.059311411	16.59043187	17.68626999	13.7434415	2.562	1.883751175
15	9.049255565	16.87204679	17.76913668	13.7594175	2.763	1.917988875
15	9.046238811	17.28618637	17.80689872	13.93139519	2.422	1.958334123
15	9.046238811	17.02631378	17.83102447	14.29410559	4.237	1.90734757
15	9.03718855	16.96522819	17.87927596	14.51010762	4.259	2.029863297
15	9.044227642	17.03770262	17.99361102	14.93595399	4.267	2.178383015
15	9.043222057	17.09464681	18.15514863	15.24421414	4.235	2.14932525
15	9.041210888	17.12053054	18.15829546	15.06976321	3.279	2.098338696
15	9.03718855	17.13399007	18.1268271	14.67394839	2.028	2.084643616
15	9.035177381	17.12260124	18.08696717	14.48074641	1.352	2.026069532
15	9.038194135	17.08947007	17.8226329	13.82545799	1.082	1.964441673
15	9.038194135	17.23441892	16.51879365	12.88790388	0.818	1.981190527
16	9.042216473	17.77590643	15.36914939	11.79760921	0.308	1.996365588
16	9.041210888	17.69618456	14.55202085	11.38726468	0.307	2.023755748
16	9.029143873	17.85148691	14.01915654	11.30073298	0.225	2.000159353
16	9.040205304	17.65787665	14.0988764	11.31954677	0.262	1.975822968
16	9.040205304	17.8069669	14.63174071	11.30217927	0.239	2.000159353
16	9.044227642	17.97262274	16.44012274	11.62050474	0.221	1.986464274
16	9.036182965	17.60507385	17.56564126	12.89399486	1.349	1.972769194
16	9.036182965	17.60921525	18.14151233	13.6624051	4.266	1.965921654
16	9.010037767	17.48704407	18.09955452	13.87924584	5.742	2.003953119
16	9.012048936	17.49222082	18.06808615	13.90638082	4.711	2.037450827
16	9.017076859	17.43527662	18.26633685	14.0321667	3.57	2.041244593
16	9.015065689	17.36176685	18.16249124	13.99725142	2.906	2.058733438
16	9.009032182	17.14641426	17.98312157	13.95528096	1.513	2.038190818
16	9.012048936	16.99525331	17.98731735	14.10096635	1.157	2.038190818
16	9.002998675	16.71467374	17.96424055	14.5609989	2.27	1.985536658
16	9.009032182	16.19285786	17.93591902	14.67972961	2.965	2.026621897
16	9.011043351	15.95990434	17.87298229	14.59259429	3.197	2.040316977
16	9.00199309	15.8998541	17.93591902	14.65078378	2.718	2.185324368
16	8.949702692	15.63480477	17.75654934	13.91975809	0.833	2.186251983
16	8.983892568	15.64101686	17.84151392	13.62802275	0.894	1.961940264
16	8.998976336	15.93505597	17.48801929	12.45517468	0.382	1.941397644
16	8.996965167	16.59975001	16.19152266	11.32387375	0.499	1.968787804
16	8.989926075	16.93727377	14.69887322	10.83694529	0.223	1.941397644
16	8.962775292	17.15159101	13.50727114	10.38481059	0.128	1.948245184
17	8.996965167	17.55020036	11.66742074	9.816959307	0.286	1.971841578
17	9.002998675	17.47979663	10.78211074	9.627433833	0.119	1.982482883
17	9.00199309	17.5129278	10.47476971	9.682789501	0.2	1.996177963
17	9.01305452	17.50153896	11.49014895	9.844153055	0.219	1.975635343
17	8.998976336	17.49636221	12.12161414	9.843851247	0.146	1.934550104
17	8.961769707	17.48290268	14.03698861	10.17592648	0.162	1.863020931
17	9.029143873	17.52224594	16.71914224	11.07760111	1.576	1.87671601
17	9.316741061	17.5615892	18.04920513	11.77907736	3.401	1.91780125
17	9.716963721	17.78315388	18.1037503	12.03450989	3.367	1.821935691
17	9.836628285	17.86494645	18.20444906	11.78040214	2.422	1.818141926
17	9.836628285	17.88979482	18.14465917	11.74470295	1.333	1.92464879
17	9.834617116	17.90946645	18.06808615	11.63748782	1.234	1.931496329
17	9.818527763	17.86805249	18.20340012	11.44156957	0.766	1.948245184
17	9.811488671	17.77694178	18.37647613	11.56530553	0.509	1.982482883
17	9.820538932	17.80489621	18.30095205	11.62850028	0.351	1.941397644
17	9.826572439	17.95502181	18.21179168	11.72745299	1.298	1.989330423
17	9.81349984	18.08961717	17.78487087	11.70031802	1.732	1.993124188
17	9.798416071	18.07615764	17.31284539	11.42456265	3.217	2.006819268
17	9.993499478	18.14552602	16.97508494	11.18112781	1.474	1.938343869
17	10.21774484	17.6630534	16.60375824	10.72223975	0.935	1.952038949
17	10.26802407	17.09361146	13.98768818	9.992299772	0.607	1.945191409
17	10.28109667	17.16815659	10.83350907	9.240833694	1.262	1.952038949
17	10.2921581	17.26651474	8.476528545	8.979490482	1.328	1.958886489
17	10.17852704	17.09982356	5.928639937	8.796961408	1.209	1.999971728
18	10.13930924	17.13709612	4.325851221	8.895310504	2.054	1.993124188
18	10.14132041	16.65358815	4.088789539	8.772358448	1.047	1.996177963
18	10.14132041	15.97232853	4.379347441	8.622330188	0.777	1.952038949
18	10.11718638	15.75490525	4.400326351	8.59187929	0.532	1.938343869
18	10.13729807	15.26518519	4.21676089	8.539961063	0.559	1.91780125
18	10.13930924	15.13887261	4.227250345	8.526814916	0.395	1.894204855
18	10.13227015	15.451548	4.378298496	8.539537736	0.707	1.887357315
18	10.13126456	14.88521212	4.265012382	8.683957121	0.679	1.89041109
18	10.13629249	14.81584373	4.18634147	8.649284873	2.141	1.89041109
18	10.13025898	14.28160367	4.35627064	8.589284529	2.381	1.914007484
18	10.13327573	13.68006592	4.373053768	8.374309441	1.664	1.838684546
18	10.13428132	13.09095235	4.368857986	8.656939691	1.637	1.815088151
18	10.15037067	12.70476719	4.13284525	8.826142327	0.726	1.811294386
18	10.16344327	12.79691325	3.877951495	8.595912403	0.42	1.856173391
18	10.1745047	13.08888166	3.753126981	8.682565623	0.403	1.849325851
18	10.17349912	13.48127891	3.752078035	8.685038865	0.257	1.863020931
18	10.15439301	13.7473636	3.768861163	8.638306187	0.531	1.872922245
18	10.15137626	14.18738691	3.801378474	8.738101581	1.981	1.873662236
18	10.15942093	14.66778883	3.615715121	8.535672996	1.696	1.907899935
18	10.1483595	14.61498603	3.372359766	8.458971518	1.636	1.914747475
18	10.1292534	13.78567151	3.121661793	8.30309532	1.145	1.935290095
18	10.1483595	11.71807962	3.008375679	8.163739966	0.878	1.914747475
18	10.14232599	10.65167018	2.996837279	8.10760039	0.754	1.873662236
18	10.01059442	8.654482025	2.580405918	7.87887951	0.548	1.832576996
19	9.470595501	7.831379595	2.785999235	7.416491265	0.275	1.740505203
19	9.051266734	7.787894939	2.788097126	7.33122557	0.243	1.757254058
19	8.518306911	7.865546111	2.841593346	7.379165484	0.224	1.753460292
19	8.356407795	7.661582365	2.846838073	7.503387521	0.262	1.746612752
19	8.698306549	7.539411186	2.815369708	7.506221344	0.427	1.743558978
19	9.223221696	7.486608389	2.81956549	7.408471893	0.221	1.716168818
19	8.81294319	7.442088383	2.88250222	7.402984536	0.263	1.705527513
19	8.878306188	7.491785134	3.027256698	7.354923105	0.257	1.702473738
19	8.904451387	7.584966541	3.331450892	7.699062742	0.539	1.688778659
19	9.043222057	9.133848597	3.499282171	8.091867427	0.664	1.729863898
19	8.963780876	9.873087761	3.694386033	8.112249038	0.536	1.732917673
19	8.824004621	10.30379293	3.800329528	8.061957401	0.616	1.750406518
19	8.85014982	9.82339101	3.850678912	8.091205037	0.521	1.716168818
19	8.887356449	8.711426218	3.791937964	8.121898972	0.406	1.716168818
19	9.093501286	8.620315509	3.720609671	8.102963659	0.313	1.702473738
19	9.292607031	9.985940798	3.773056945	8.117375814	0.442	1.688778659
19	9.276517678	10.76141718	3.870608876	8.206200467	0.664	1.736711438
19	9.414282765	12.57017182	3.807672147	8.295809029	1.133	1.747352743
19	9.524897068	13.04436165	4.172705179	8.241296042	1.224	1.825729456
19	9.610371756	11.92307872	4.198928816	8.217959089	1.224	1.838684546
19	9.489701608	11.09894094	4.336340676	8.300030378	0.859	1.842478311
19	9.544003174	10.74381624	4.296480747	8.358643196	0.555	1.859227165
19	9.704896706	11.10411768	4.58913654	8.317276357	0.69	1.866074705
19	9.733053074	10.44667109	4.379347441	8.223387673	0.339	1.849325851
20	9.277523263	9.97351661	3.960818189	8.098385701	0.312	1.86986847
20	8.88534528	10.16195012	3.758371708	8.364075753	0.445	1.886617325
20	8.934618924	10.23235385	3.766763272	8.532016354	0.499	1.866074705
20	9.481656931	10.41768132	3.948230843	8.651111615	0.561	1.859227165
20	9.968359864	13.0919877	4.604870723	8.848115589	0.936	1.86986847
20	9.968359864	15.53437592	7.340520574	8.943568116	0.822	1.903366179
20	10.01863909	16.15454995	10.37511989	9.712338946	1.4	1.917061259
20	10.02768935	16.49000302	12.70482783	10.44107169	1.785	1.962680254
20	10.04780105	16.67947188	14.93803279	10.81740636	2.395	1.93908386
20	10.08903001	16.73848677	16.2869767	11.21623133	1.332	1.931496329
20	10.11115287	16.79025422	17.07473477	11.67198375	0.994	1.931496329
20	10.14534275	16.83580957	17.37788001	11.81314599	1.832	1.877456001
20	10.15137626	16.83995097	17.57613071	11.81350657	0.743	1.914747475
20	10.17249353	16.85444585	17.91913589	11.88707241	1.404	1.887357315
20	10.1875773	16.86687004	18.14256128	12.00085664	2.3	1.901052395
20	10.19562198	16.83063283	18.34920354	12.38310596	2.701	1.901052395
20	10.2006499	16.80578445	18.4866154	12.61598942	4.093	1.921595015
20	10.20567782	16.78404212	18.64395723	12.92129423	3.85	1.952038949
20	10.23081744	16.79336026	18.64710406	12.72097831	2.944	1.958886489
20	10.23081744	16.77679468	18.63032094	12.31509817	2	2.003765494
20	10.24187887	16.77368863	18.20340012	11.41855031	0.936	1.958886489
20	10.24791237	16.71467374	17.16704197	10.77435813	0.685	1.931496329
20	10.26199056	16.73538072	15.73418242	10.690723	0.582	1.958886489
20	10.24087328	16.73434537	13.27964997	10.247031	0.276	1.986276649
21	10.22880627	16.71053235	11.97266388	10.09392588	0.312	1.958886489
21	10.24791237	16.70121421	11.51007892	9.742554753	0.288	1.952038949
21	10.25394588	16.68257792	10.98350828	9.687559667	0.207	1.958886489
21	10.26701848	16.68257792	11.11567541	9.779939307	0.354	1.938343869
21	10.26701848	16.66911839	12.25797705	10.18021455	0.24	1.945191409
21	10.25595705	16.65358815	15.25796117	10.90647405	0.32	1.900312405
21	10.24690679	16.65151746	17.48906824	12.23941966	0.871	1.900312405
21	10.24389004	16.71053235	18.16039335	13.24330415	2.234	1.931496329
21	10.2398677	16.69810816	18.44570653	13.30227358	3.68	1.958886489
21	10.24288445	16.70121421	18.56633526	12.84302097	2.532	1.968787804
21	10.23483978	16.6587649	18.53172006	12.42350066	2.699	2.031155653
21	10.24087328	16.68671932	18.74780283	12.1967042	4.208	1.986276649
21	10.23584536	16.63081048	18.67962137	11.88735436	2.645	1.982482883
21	10.23483978	16.62563373	18.60514624	12.11691792	2.745	1.996177963
21	10.23383419	16.68154258	18.73521549	12.21261349	1.61	1.89725863
21	10.23483978	16.46515464	18.72997076	12.02712907	1.613	1.913267494
21	10.21875042	16.44962441	18.71108974	12.18252317	2.693	1.953612743
21	10.21573367	16.50139185	18.70584501	12.38760529	4.079	1.993957991
21	10.20668341	16.50139185	18.64395723	11.69463051	1.67	2.009873043
21	10.20366665	16.46308394	17.8247308	11.29676577	0.876	2.016720583
21	10.19461639	16.42581138	14.50901409	10.59499565	0.609	1.992384198
21	10.20467224	16.4599779	10.40239247	9.858063248	0.468	1.961940264
21	10.16646002	16.43823557	7.71394517	9.226778149	1.129	2.033469437
21	9.979421294	16.42477603	6.013604522	8.531753455	0.727	2.071500902
22	9.942214665	16.41338719	4.838785568	8.614608652	0.203	2.085195982
22	9.972382202	15.12748377	4.348928022	8.337704823	0.22	2.071500902
22	9.886907514	12.140502	4.101376885	8.360257868	0.124	2.101944836
22	9.858751146	11.25527863	4.10032794	8.484601423	0.14	2.088249756
22	9.980426879	11.57934286	4.201026707	8.637706542	0.283	2.016720583
22	9.985454802	13.78567151	4.537738211	9.049924667	0.286	1.999231738
22	9.910035959	15.7497285	5.125147688	9.071509541	0.495	1.978689118
22	9.975398956	15.64101686	6.859054591	9.459363769	2.209	1.975635343
22	9.973387787	15.29417496	7.441219341	9.683079392	2.723	2.023568123
22	9.956292849	15.10884749	7.408702031	9.744102707	0.727	2.054012057
22	9.94322025	15.38217962	7.401359412	9.387785094	0.412	1.961940264
22	9.951264926	15.68864291	7.333177955	9.377531543	0.428	1.961940264
22	9.94322025	16.72916863	7.161150894	9.264950583	0.549	1.961940264
22	9.94322025	17.18782822	7.620589021	9.242699347	0.552	1.948245184
22	9.983443632	17.33381243	8.297158865	9.371562087	1.264	1.968047813
22	10.05685131	17.08739937	9.282118685	9.754712867	2.106	1.927702564
22	9.969365448	17.01285425	10.33421102	10.02932374	3.648	2.18181204
22	9.94120908	17.03149053	10.92162049	9.85589976	3.223	2.291466491
22	9.946237003	16.89275376	10.55344062	9.812000905	2.561	2.194860942
22	9.925119727	16.94555656	9.062889076	9.357514486	3.131	1.952226574
22	9.94120908	16.92588493	6.981781214	9.06252597	1.193	1.87597602
22	9.961320772	16.64841141	5.286685294	9.053605144	1.147	1.852379625
22	9.983443632	16.79336026	4.632143306	8.879640287	0.745	1.951298959
22	9.98947714	15.91538434	4.245082418	8.661474766	0.732	2.030415663
23	10.08601326	14.1532204	4.038440156	8.464172956	0.431	2.030415663
23	10.08701884	12.53082856	4.066761684	8.435830746	0.287	2.126281221
23	10.08601326	12.6395402	4.038440156	8.489559825	0.201	2.105738601
23	10.08400209	12.14878479	4.185292525	8.538585455	0.192	2.037263202
23	10.06489598	11.93136151	4.638436979	8.596112556	0.061	2.023568123
23	10.08098534	13.39016821	5.324447332	8.851306022	0.153	1.982482883
23	10.0246726	15.33869496	5.408362972	9.37031197	0.667	1.964994038
23	10.07495183	16.23427182	5.333887842	9.508279799	1.535	1.945191409
23	10.03673961	15.74765781	5.493327557	9.293971073	0.837	1.976375334
23	10.04478429	15.19271076	5.601368943	8.9355408	1.152	2.020514348
23	10.04780105	15.61202709	5.278293731	8.716826462	1.171	1.999971728
23	10.04780105	16.0054597	4.961512191	8.637287188	0.488	2.006819268
23	10.02366702	15.92263178	4.965707973	8.458371873	0.459	1.999971728
23	10.0377452	15.91020759	4.983540046	8.332099921	0.708	2.038003193
23	10.02970052	16.13798437	5.251021148	8.307555733	0.713	2.020514348
23	10.02970052	16.23634252	5.125147688	8.351576106	0.96	1.938343869
23	10.00556649	16.03237877	5.8908779	8.735032667	1.158	1.938343869
23	10.03673961	16.18043367	6.179337911	8.889584084	3.217	1.856173391
23	10.04679546	16.8047491	6.388078064	8.927693773	1.829	1.900312405
23	10.03271728	17.24270172	6.023045032	8.896580485	0.841	1.88356355
23	10.03573403	17.22095939	5.26675533	8.785085241	1.588	1.863020931
23	10.00958883	17.45184221	4.435990498	8.55178243	0.763	1.853119616
23	9.986460386	17.72413899	3.988090772	8.535684913	0.516	1.91095371
23	10.02266143	17.84113342	3.594736211	8.390121039	0.348	1.976375334
24	10.07997975	17.85045156	3.740539635	8.492330903	0.471	1.962680254
24	10.14735392	17.81939109	4.161166778	8.526219243	0.322	2.003025503
24	10.08601326	17.75002271	4.618507014	8.662199902	0.229	1.975635343
24	9.996516232	17.53984687	4.603821777	8.782502398	0.129	1.961940264
24	9.998527401	17.68893712	5.685284583	8.998621976	0.108	1.971841578
24	10.09808027	17.82249714	7.425485159	9.234699837	0.17	1.927702564
24	10.14433716	17.92499669	11.53840044	10.0314523	0.792	1.91095371
24	10.10713053	17.92189064	14.50376936	10.7154435	1.873	2.090480237
24	10.20165548	17.85045156	14.8205509	10.82868685	1.768	2.133973073
24	10.2529403	17.98090553	13.93209406	10.26957213	0.855	2.140820613
24	10.2529403	17.97365809	13.35307615	9.981752358	0.491	1.978136753
24	10.25997939	17.99125902	13.40342553	10.0096085	0.697	1.914007484
24	10.24389004	17.93845622	13.70447289	10.06652801	1.133	1.955092724
24	10.23685094	17.87219389	14.92964123	10.22915757	0.968	1.930756339
24	10.2529403	17.88668877	15.20446495	10.08117923	1.673	1.88282356
24	10.24690679	17.90118366	15.7173993	10.45468404	2.539	1.87597602
24	10.2398677	17.86598179	15.96075465	10.64071331	3.162	1.861540949
24	10.24389004	17.88979482	16.07404076	10.63365813	4.849	1.8554334
24	10.24187887	17.88565343	16.28382986	10.81896623	4.307	1.903366179
24	10.23483978	17.87633528	16.40970332	10.58553793	3.73	1.923908799
24	10.24891796	17.80075481	16.22194208	10.62594454	1.687	1.951298959
24	10.25997939	17.78522458	15.73523137	10.46602728	1.323	1.954352733
24	10.26400173	17.77694178	14.82894246	10.20021969	1.227	1.947505193
24	10.25495147	17.85355761	13.34992931	9.005422195	0.947	1.951298959
25	10.26199056	17.78315388	12.71846413	8.805466852	0.724	1.954352733
25	10.25796822	17.94052692	12.12895676	8.845207103	0.466	1.961200273
25	10.24791237	18.04302647	11.29399614	8.946876095	0.489	1.923908799
25	10.07796858	17.96019855	11.31812189	8.706271102	0.494	1.933810114
25	10.08500767	18.13724322	11.37896073	9.040404197	0.571	1.933810114
25	10.08802443	18.25423766	11.23735309	8.785747631	0.454	1.926962574
25	10.08400209	18.27080324	11.58979877	9.166429141	0.296	1.940657653
25	10.05685131	18.25423766	12.76147089	9.2729779	0.747	1.920115034
25	10.1483595	18.43956512	14.30342077	9.398042618	0.739	1.954352733
25	10.20567782	18.55863025	14.67789431	9.143327279	2.739	1.961200273
25	10.23282861	18.47683769	14.84887243	8.945656942	2.669	1.957406508
25	10.24690679	18.43542373	15.12159826	8.839766601	2.963	1.91780125
25	10.25193471	18.43645908	15.14047927	8.80750485	2.247	1.907899935
25	10.25193471	18.44370652	14.8205509	8.655183639	0.589	1.877456001
25	10.26299614	18.52860513	14.45761576	8.695225698	0.479	1.888097306
25	10.28713017	18.58865537	13.73803915	8.776634597	0.424	1.901792386
25	10.2720464	18.64870561	14.28663764	9.00487735	0.716	1.853859607
25	10.27707433	18.74085167	14.26670768	9.237400226	1.126	1.870608461
25	10.26098497	18.72739214	12.44678724	9.270688921	1.376	1.874402226
25	10.19059405	18.67769539	10.08036621	9.201646233	0.448	1.901052395
25	10.17048236	18.47683769	6.647167601	9.080018957	0.561	1.887357315
25	10.0638904	17.72103294	4.597528104	8.940483312	0.474	1.897998621
25	10.15841535	17.10810635	3.735294907	8.631623513	0.803	1.92538878
25	10.12523106	15.82945037	3.371310821	8.440471449	1.105	1.92464879
26	10.15942093	14.6501879	3.037746153	8.290925289	0.576	1.914747475
26	10.17048236	13.36842588	2.954879459	8.288091466	0.402	1.907899935
26	10.15037067	12.57534857	2.964319969	8.303589337	0.334	1.90410617
26	10.18556613	12.58570206	2.932851604	8.351227442	0.438	1.89041109
26	10.15037067	12.60123229	3.036697208	8.362503964	0.517	1.90410617
26	10.14232599	12.10219409	3.15732594	8.376916119	0.471	1.863020931
26	10.1031082	11.70151404	3.271660999	8.349177526	0.248	1.873662236
26	10.21271691	11.81229638	3.248584198	8.360936148	0.387	1.856173391
26	10.25595705	13.80430779	3.076557137	8.46001038	0.968	1.859967156
26	10.22277276	14.55907719	3.140542812	8.495466536	1.034	1.873662236
26	10.16746561	14.79513676	3.417464423	8.473697399	0.879	1.880509776
26	10.15640418	14.63155162	3.788791128	8.388792286	1.166	1.859967156
26	10.18556613	14.53733486	3.70907127	8.287123294	1.192	1.866814696
26	10.1875773	14.53629951	3.68809236	8.271625423	1.065	1.89041109
26	10.18154379	15.24758425	3.781448509	8.261132808	0.699	1.88356355
26	10.17349912	15.89467736	3.829700002	8.260047092	0.835	1.87671601
26	10.23685094	15.71866803	3.880049386	8.354116066	1.473	1.859967156
26	10.25092913	16.09657041	4.000678118	8.49588589	2.722	1.859967156
26	10.27405757	16.65980025	3.876902549	8.746438652	2.736	1.859967156
26	10.25796822	16.84616306	3.906273023	8.830258048	1.47	1.907899935
26	10.2660129	16.65565885	3.812916874	8.888690576	0.752	1.935290095
26	10.28411342	16.56765419	3.71851178	8.860168075	1.045	1.92464879
26	10.285119	16.61528024	3.658721886	8.813615687	0.711	1.952038949
26	10.23383419	16.21356484	3.232850015	8.828631459	0.512	1.972581569
27	10.07595741	15.31384659	2.98739677	8.791003869	0.29	1.907899935
27	10.05282897	14.74854605	3.121661793	8.852450511	0.219	1.849325851
27	10.12120872	14.49074416	3.15732594	8.857757577	0.275	1.846272076
27	10.04578988	13.82087338	3.234947906	8.881274821	0.36	1.818881917
27	9.895957775	14.08178132	3.469911697	8.998861039	0.3	1.818881917
27	9.932158819	15.57682523	4.054174338	9.155160563	0.489	1.825729456
27	10.17048236	16.39682161	5.261510603	9.709505122	1.889	1.832576996
27	10.14634833	16.66808304	5.928639937	10.00111894	3.094	1.884303541
27	10.15539859	16.16283274	5.950667793	10.2371968	3.568	1.850065841
27	10.10612495	15.59649686	6.132135363	10.24063425	1.448	1.850065841
27	10.13830366	15.41634614	5.868850044	10.12732815	0.751	1.843218301
27	10.14433716	15.11091819	5.256265875	10.08752913	1.078	1.805186837
27	10.13227015	15.60270895	5.080043032	9.973740931	0.708	1.729863898
27	10.06690715	15.14094331	5.008714738	10.06141712	1.031	1.761047823
27	9.905008036	15.0477619	5.18283969	10.31196591	0.831	1.767895363
27	9.889924267	15.05708004	5.317104714	10.20897214	0.873	1.740505203
27	9.898974528	14.96596934	5.475495484	10.23906246	2.275	1.761047823
27	9.880874006	14.39963345	5.964304084	10.4076027	3.915	1.770949137
27	9.973387787	14.25364924	6.09332438	10.42044704	2.752	1.764101597
27	10.03573403	14.43172927	5.659060945	10.23918397	1.857	1.723756349
27	10.06590157	15.03223167	5.046476776	9.950043397	0.914	1.757994048
27	10.06590157	15.69381966	4.425501043	9.458050906	0.41	1.737451428
27	10.14634833	15.9081369	4.072006411	9.223964187	0.541	1.65528095
27	10.00456091	14.89245956	3.556974173	8.983124104	0.158	1.640845879
28	10.03372286	13.9523627	3.784595346	9.019728722	0.46	1.6271508
28	9.892941021	13.20380539	3.729001235	9.050963529	0.312	1.675083579
28	9.97640454	13.32597657	3.756273817	9.040470915	0.284	1.723016358
28	10.10713053	13.12926027	4.024803864	9.262442403	0.453	1.723016358
28	10.15137626	13.63761661	4.394032678	9.409758357	0.641	1.705527513
28	10.15338743	14.93180282	5.539481159	9.525835531	0.588	1.719222593
28	10.10009144	15.61823918	8.551003675	10.1544671	1.628	1.712375053
28	9.970371033	15.90710155	10.88700529	10.70591509	1.775	1.723016358
28	9.944225834	16.0520504	12.42161255	10.74547107	1.265	1.726070133
28	9.963331941	16.10174715	12.88209962	10.67328878	0.743	1.777056687
28	9.963331941	16.0520504	13.39608292	10.5822927	0.478	1.732917673
28	9.947242588	16.08725227	14.66111118	10.58663159	0.452	1.740505203
28	9.960315187	16.43512952	14.9820885	10.92738859	0.884	1.784644217
28	9.970371033	16.58732582	15.38173674	11.22195775	1.205	1.798339297
28	9.953276095	17.04702076	15.96495043	11.56512921	1.122	1.818881917
28	9.970371033	17.39696871	16.26285095	11.72239294	1.775	1.784644217
28	10.17953262	17.68583107	16.30375983	12.17585638	3.014	1.832576996
28	10.1875773	17.7075734	16.58382827	12.43449126	4.642	1.818881917
28	10.21975601	18.01714274	16.73487643	12.50360067	3.239	1.839424536
28	10.24087328	18.03474368	16.73802326	12.37244895	2.715	1.777796677
28	10.2529403	17.9591632	16.29641721	12.16290642	1.285	1.764101597
28	10.285119	17.78936597	14.96635432	11.40878681	1.192	1.723016358
28	10.28310783	17.85666365	13.48839012	10.78853519	0.549	1.719962583
28	10.23584536	17.77280039	12.27685807	10.32970988	0.375	1.713115044
29	10.05785689	18.33603023	11.07266864	11.12537662	0.159	1.569316706
29	10.25595705	18.38365628	10.86602638	11.13460323	0.198	1.57847803
29	10.25595705	18.40746931	10.83980274	11.44015108	0.226	1.572370481
29	10.24087328	18.49236792	11.12301803	11.37780298	0.168	1.5929131
29	10.26701848	18.33085348	11.58245616	11.37870443	0.189	1.57921802
29	10.3052307	18.25216696	13.00167941	12.30293211	0.394	1.582271795
29	10.2921581	18.32464139	15.34082786	13.80694998	1.134	1.616509495
29	10.30221394	18.39608047	16.53242995	14.97352678	3.447	1.664442274
29	10.29014693	18.33085348	16.7411701	15.22015603	4.793	1.726070133
29	10.30724186	18.42714094	16.78312792	15.33146701	3.087	1.756514067
29	10.30623628	18.44163582	16.90900138	15.19066138	2.755	1.801393072
29	10.3112642	18.4664842	17.02648327	15.13445906	2.884	1.87597602
29	10.31025862	18.48408513	17.031728	15.14392473	2.497	1.831837006
29	10.31025862	18.51618095	16.96564444	14.9508403	2.691	1.982482883
29	10.30724186	18.52342839	17.00655331	15.07373358	2.528	1.968787804
29	10.2981916	18.91996704	17.04536429	15.16334214	2.318	1.989330423
29	10.29718602	19.00693636	17.21529346	15.78154781	3.95	1.930756339
29	10.29316368	19.03592613	17.1124968	16.02305426	4.928	2.179498256
29	10.30120836	19.07837544	17.01284698	16.05887497	3.961	2.158768011
29	10.30221394	19.08251683	16.99186807	16.01129961	4.284	1.983222874
29	10.30020277	19.0121131	16.87438618	15.39834621	2.352	1.95277894
29	10.30422511	19.02143124	16.58173038	14.82325946	1.493	1.993864179
29	10.30925303	18.75741726	16.43173118	14.35261675	1.276	1.891151081
29	10.31025862	18.48408513	15.81600017	13.43713358	0.73	1.802133062
30	10.31327537	18.78330098	16.02054454	13.54296118	0.686	1.815828142
30	10.32132005	18.71703865	15.3555131	12.91462745	0.39	1.859967156
30	10.3243368	18.6166098	14.71146057	13.01225538	0.366	1.815828142
30	10.31930888	18.47476699	14.73873315	13.22512178	0.425	1.832576996
30	10.32132005	18.49961536	15.49187601	13.37406432	0.451	1.777796677
30	10.31830329	18.74188702	16.21459946	14.20301976	0.374	1.787697992
30	10.30221394	18.88269448	17.23837026	15.05181196	0.938	1.780850452
30	10.32534239	19.05559776	17.97263211	15.93714604	1.624	1.87671601
30	10.31629213	19.27198569	18.21179168	16.30020907	4.543	1.921595015
30	10.32132005	19.30925826	17.98941524	16.19498112	4.152	1.938343869
30	10.33037031	19.34446012	17.63906744	15.9792809	2.661	1.91095371
30	10.32835914	19.32582384	17.51214504	15.64376425	3.796	1.934550104
30	10.31629213	19.33928338	17.53731973	15.55047521	2.988	1.92464879
30	10.31930888	19.34653082	17.5551518	15.37505611	1.923	1.976375334
30	10.32132005	19.37034385	17.56564126	15.41244464	1.9	1.938343869
30	10.31930888	19.35999036	17.54256446	15.40786271	1.879	1.955832714
30	10.3052307	19.28751593	17.51948766	15.79614423	3.296	1.974989165
30	10.31428096	19.26473825	17.54780918	16.20161297	4.918	2.701599912
30	10.32333122	19.28958663	17.6034033	16.1626606	4.214	2.66116085
30	10.31528654	19.29683407	17.64011639	15.83709966	2.641	1.952038949
30	10.31930888	19.31132895	17.65794846	15.22070882	3.071	1.996917954
30	10.31226979	19.19536987	17.4859214	14.32229134	1.328	1.907899935
30	10.31025862	19.09597637	16.96984022	13.52143905	0.512	1.859967156
30	10.30020277	18.78330098	15.4614566	13.06810109	0.291	1.880509776
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Uncertainty relates to the increased difficulty of reliably predicting VRE resource availability at specific points of the day. Historically, power systems managed this by scheduling significant amounts of spinning reserves to back up VRE generation, leading to high fuel and availability costs.

Experience from power systems across the world has shown that the impact of uncertainty can be reduced by improving market design with gate-closures closer to real-time and requiring the use of improved forecasting techniques. For example, Ontario’s IESO is currently implementing a market reform to improve system operations in the face of high VRE penetration. This includes the introduction of a day-ahead market to complement its existing real-time market.

Technical challenges at high shares of non-synchronous generation

High shares of VRE can create operational challenges, particularly short-term flexibility related to power system stability on the sub-second timescale. System inertia, a property derived from synchronous generators, acts to mitigate the rate of change of frequency following a contingency event in the power system.

VRE do not directly contribute to providing inertia to the power system since they are connected to the grid via power electronic converter devices, hence the term “non-synchronous”. VRE generators do not have a direct, electro-mechanical coupling to the grid, which makes them different to traditional, synchronous generators. As VRE displaces thermal generation, system inertia will be reduced, causing the system to be less stable. Currently, a few countries/regions with relatively small power system, such as Ireland and South Australia, are in the phase where the inertia is becoming a key issue.

One of the reliability measures used to maintain sufficient synchronous inertia is the establishment of a maximum limit of system non-synchronous system penetration (SNSP), which indicates the maximum share of non-synchronous generation (i.e. VRE), at any instance, that does not pose a security risk to the power system.

A SNSP limit is system specific and has to be established based on thorough analysis and testing. Ireland and Northern Ireland managed to raise the SNSP limit from 50% in 2015 to 65% with a target of 75% by 2020.

An option to overcome this issue is the delivery of synthetic inertia (or referred to as inertia-based fast frequency response) by VRE sources. First experiences are covered in pilot trials, and clear technical requirements and compliance procedures are needed to take these up in grid codes.

An alternative option is to provide additional inertia by means of other assets such as synchronous condensers installed by the transmission operator. These can also help to mitigate other technical issues related to higher shares of VRE such as loss of system strength. The case of South Australia is a good example of this.

A complementary option is one based on smarter measurement of inertia to allow system operators to recognise the real-time capability of the system in dealing with possible contingency. Japan and Great Britain are front-runners in the introduction of real-time inertia monitoring systems to overcome challenges associated with high VRE penetration.

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