Historical energy data in OpenNEM (wildly) inconsistent with CER data

[aleith]

I'm not sure of the data source for the opennem generation data for coal and gas but because I was interested in emissions intensity I started looking at the Clean Energy Regualtor's generation by facility data for 2019-20 (FY20).

It's probably to be expected that there will be differences in emissions data between sources due to the rubbery nature of emissions intensity indexes (used in openNEM to convert the energy [MWh] database to emissions [tCO₂-e] for the UI views/reporting), measurement and national reporting. What I wasn't expecting was big differences in the underlying energy (MWh) data between openNEM and the CER data.

I've only compared 4 facilities so far, all gas and all in WA. But some of the comparable numbers are close and others are dramatically different.

Here's a sample of the reporting differences (link to excel file)

Reporting entity	Facility name	State	Electricity production [MWh]	OPENNEM Energy FY20 [MWh]	delta	% Delta A	% Delta B
AGL ENERGY LIMITED	Kwinana Swift Power Station	WA	123,007	122,394	-613	0%	-1%
ELECTRICITY GENERATION AND RETAIL CORPORATION	Kwinana Power Station	WA	793,439	1,414,799	621,360	78%	44%
INTERNATIONAL POWER (AUSTRALIA) HOLDINGS PTY LIMITED	Kwinana Cogeneration Plant	WA	940,981	241,884	-699,097	-74%	-289%
NEWGEN KWINANA HOLDINGS PTY LTD	Kwinana Gas Fired Power Station	WA	1,724,343	1,695,385	-28,958	-2%	-2%

I guess next step is to DL and compare with AEMO SCADA data.

[aleith]

I should add that CER data is widely regarded as having lots of issues, so I'm not pointing the finger at OpenNEM at all, just raising the issues for further discussion/investigation.

[aleith]

I've now compared all the fossil generation on the SWIS and most of the comparisons for energy and emissions between CER and openNEM data are out by at least a magnitude of ~10%, some much greater than that (up to 153%).

I've checked and double checked that I'm using the correct FY21 data from openNEM, and the CER excel file states that it's 2020-21 (they would have to use financial years for reporting wouldn't they?). There's also a few facilities I can't match the names of, small facilities though.

Excel file here.

Numbers file here

Facility name	Electricity production	Total emissions	Emission intensity	Primary fuel	OpemNEM Facility	Tech.	Capacity	Emissions Intensity	OpemNEM Electricity	OpemNEM Emissions (Inferred)	Energy Difference CER vs OpenNEM	Energy Difference [%]	Emissions Difference	Emissions Diff [%]
Bluewaters Power 1	1,613,610	1,219,437	0.75	Black Coal	Bluewaters G1	Coal	217	880	1,466,669	1,290,669	146,941	9.5%	-71,232	-5.7%
Bluewaters Power 2	1,689,841	1,256,311	0.74	Black Coal	Bluewaters G2	Coal	217	910	1,535,867	1,397,639	153,974	9.5%	-141,328	-10.7%
Collie Power Station	1,043,412	958,188	0.92	Black Coal	Collie G1	Coal	318	910	950,734	865,168	92,678	9.3%	93,020	10.2%
Muja Power Station	3,587,410	3,262,123	0.91	Black Coal	Muja C & D Total (4 units)	Coal	814.6	920	3,342,375	3,074,985	245,035	7.1%	187,138	5.9%
Kalamunda Power Station	0	1	0.00	Diesel
Ravensthorpe Power Station	69	50	0.72	Diesel
Alinta Pinjarra Generation Facility	1,594,393	1,087,443	0.68	Gas	Pinjara	OCGT	286	670	1,558,189	1,043,987	36,204	2.3%	43,456	4.1%
Cockburn Power Station	130,959	52,840	0.40	Gas	Cockburn	CCGT	250	390	123,474	48,155	7,485	5.9%	4,685	9.3%
Kalgoorlie Gas Turbine Station	5,433	5,283	0.97	Gas
Kalgoorlie Power Station	279,941	156,822	0.56	Gas
Kambalda Power Station	284,226	155,829	0.55	Gas	Kambalda	OCGT	23	960	131,827	126,554	152,399	73.3%	29,275	20.7%
Kemerton Power Station	131,827	88,548	0.65	Gas	Kemerton	OCGT	309	700	950,734	665,514	-818,907	-151.3%	-576,966	-153.0%
Kwinana Cogeneration Plant	780,046	403,357	0.52	Gas	Kwinana Cogen	OCGT?	42	580	241,876	140,288	538,170	105.3%	263,069	96.8%
Kwinana Gas Fired Power Station	2,027,187	795,906	0.39	Gas	Newgen Kwinana	CCGT	335	540	1,989,822	1,074,504	37,365	1.9%	-278,598	-29.8%
Kwinana Power Station	669,920	355,381	0.53	Gas	Kwinana	OCGT	296	520	1,227,361	638,228	-557,441	-58.8%	-282,847	-56.9%
Kwinana Swift Power Station	34,511	20,977	0.60	Gas	Kwinana Swift	OCGT	116	578	34,364	19,877	147	0.4%	1,100	5.4%
Mungarra Gas Turbine Station	30,926	25,262	0.82	Gas	Mugarra	OCGT	117	780	30,585	23,856	341	1.1%	1,406	5.7%
Newgen Neerabup Power Station	200,465	124,564	0.60	Gas	Neerabup	OCGT	342	600	198,685	119,211	1,780	0.9%	5,353	4.4%
Parkeston Power Station	261,661	146,132	0.56	Gas	Parkeston	OCGT	68	600	46,994	28,196	214,667	139.1%	117,936	135.3%
Pinjar Gas Turbine Station	559,454	497,194	0.89	Gas	Pinjar	OCGT / Distillate	576	820	552,704	453,217	6,750	1.2%	43,977	9.3%
Wagerup Power Station	334,356	189,349	0.55	Gas	Wagerup	OCGT	408	560	387,887	217,217	-53,531	-14.8%	-27,868	-13.7%

[aleith]

any ideas could possibly be going on here @simonhac ?

There are very large discrepancies in some cases, very similar numbers in other cases and some in between.

Facility name	WA	Electricity (MWh)	emissions (tCO2e)	OpemNEM [MWh]	OpemNEM [tCO2e]	Energy Difference / (CER + OpenNEM)[%]	Emissions Diff / (CER + OpenNEM)
Bluewaters Power 1	WA	1,613,610	1,219,437	1,466,669	1,290,669	4.8%	-2.8%
Bluewaters Power 2	WA	1,689,841	1,256,311	1,535,867	1,397,639	4.8%	-5.3%
Collie Power Station	WA	1,043,412	958,188	950,734	865,168	4.6%	5.1%
Muja Power Station	WA	3,587,410	3,262,123	3,342,375	3,074,985	3.5%	3.0%
Kalamunda Power Station	WA	0	1
Ravensthorpe Power Station	WA	69	50
Alinta Pinjarra Generation Facility	WA	1,594,393	1,087,443	1,558,189	1,043,987	1.1%	2.0%
Cockburn Power Station	WA	130,959	52,840	123,474	48,155	2.9%	4.6%
Kalgoorlie Gas Turbine Station	WA	5,433	5,283
Kalgoorlie Power Station	WA	279,941	156,822
Kambalda Power Station	WA	284,226	155,829	131,827	126,554	36.6%	10.4%
Kemerton Power Station	WA	131,827	88,548	950,734	665,514	-75.6%	-76.5%
Kwinana Cogeneration Plant	WA	780,046	403,357	241,876	140,288	52.7%	48.4%
Kwinana Gas Fired Power Station	WA	2,027,187	795,906	1,989,822	1,074,504	0.9%	-14.9%
Kwinana Power Station	WA	669,920	355,381	1,227,361	638,228	-29.4%	-28.5%
Kwinana Swift Power Station	WA	34,511	20,977	34,364	19,877	0.2%	2.7%
Mungarra Gas Turbine Station	WA	30,926	25,262	30,585	23,856	0.6%	2.9%
Newgen Neerabup Power Station	WA	200,465	124,564	198,685	119,211	0.4%	2.2%
Parkeston Power Station	WA	261,661	146,132	46,994	28,196	69.5%	67.7%
Pinjar Gas Turbine Station	WA	559,454	497,194	552,704	453,217	0.6%	4.6%
Wagerup Power Station	WA	334,356	189,349	387,887	217,217	-7.4%	-6.9%

[nc9]

related #104