Understanding policy evolution using institutional grammar: net metering policies in the United States

Figures & data

Table 1. Selection criteria and cases.

		Renewable Portfolio Standard
		Yes	No
Electricity market regulation	Regulated	California	Arkansas
	Deregulated	Illinois, Virginia	No States Observed

Table 2. Coding example from Illinois.

#	Illinois, 2021 P.A. 102-662, § 90-50	Syntactic Elements		Rule Type		Institutional Type		Type of Change (0 = Termination; 1 = Addition; 2 = Calibration)	Change (0/1)
		Values	Change	Post-Change	Pre-Change	Post-Change	Pre-Change
1	The electricity provider shall continue to apply those excess kilowatt-hour or monetary energy credits to subsequent billing periods to offset any customer-generator consumption in those billing periods until all credits are used or until the end of the annualized period.	Addition to Direct Object; Removal of Execution Constraint	Direct Object; Context (Execution Constraint)	Payoff	Payoff	Reg	Reg	2	1
2	For customers with transmission or capacity charges not charged on a kilowatt-hour basis, the electricity provider shall prepare a reasonable approximation of the kilowatt-hour equivalent value.	Statement Added.	Statement	Choice	N/A	Reg	N/A	1	1
3	At the end of the year or annualized over the period that service is supplied by means of net metering, or in the event that the retail customer terminates service with the electricity provider prior to the end of the year or the annualized period, any remaining credits in the customer's account shall expire.	Statement Removed.	Statement	N/A	Payoff	N/A	Reg	0	1
4	An electricity provider shall charge or credit for the net electricity supplied to eligible customers or provided by eligible customers whose electric supply service is provided based on hourly pricing in the following manner:								0
Note: Green text identifies text added compared to the prior policy; Red text identifies text removed compared to the prior policy; Black text identifies text maintained compared to the prior policy.

Figure 1. Coding approach.

Table 3. Syntactic elements calibrated in constitutive rules.

	Arkansas	Illinois	California	Virginia	All States
Constituted Entity	1	0	10	0	11
Modal	0	0	0	0	0
Constitutive Function	0	0	0	0	0
Constituting Properties	18	5	16	10	49
Context	1	0	22	4	27

Table 4. Syntactic elements calibrated in regulative rules.

	Arkansas	Illinois	California	Virginia	All States
Attributes	1	0	29	19	49
Deontic	4	0	1	0	5
Aim	0	1	1	1	3
Direct Object	0	13	16	11	40
Indirect Object	0	3	4	6	13
Activation Conditions	1	14	0	8	23
Context	10	8	68	15	101

Figure 2. Change in policy extent over time.

Figure 3. Policy maintenance, additions, and termination in words over time.

Figure 4. Constitutive and regulative Maintenance, additions, termination, and calibration over time.

Figure 5. Rule type maintenance, additions, termination, and calibration over time.

Table A1. Timing and total count of policy amendment for each state.

	1995	1996	1997	1998	1999	2000	2001	2002	2003	2004	2005	2006	2007	2008	2009	2010	2011	2012	2013	2014	2015	2016	2017	2018	2019	2020	2021	2022	2023	Total
Arkansas							1	0	0	0	0	0	1	0	0	0	0	0	1	0	1	0	0	0	1	0	0	0	1	6
Illinois													1	0	0	0	1	1	0	0	0	0	1	0	0	0	1	0	0	5
California	1	0	0	1	0	1	1	1	0	0	1	1	0	1	1	1	1	1	1	1	1	0	0	1	0	0	0	1	0	17
Virginia					1	0	0	0	0	1	0	1	1	0	1	0	1	0	1	0	1	0	1	0	1	1	0	0	0	11

1 identifies year in which a policy amendment is observed; 0 identifies year in which no policy amendment is observed.

Table A2. Descriptive statistics of additions, terminations, and calibrations across states.

	Additions			Terminations			Calibration
	Total	Mean	St. Dev.	Total	Mean	St. Dev.	Total	Mean	St. Dev.
Arkansas	96	19.20	19.60	31	6.20	10.06	40	8.00	6.89
Illinois	117	23.4	26.7	10	2.0	2.0	48	9.6	8.0
California	142	8.35	10.90	23	1.35	2.55	187	11.00	15.10
Virginia	139	11.58	20.22	1	0.08	0.29	48	4.00	6.24
All States	494	12.67	17.70	65	1.63	4.12	323	8.08	11.26

The counts above represent the changes observed in the policies and do not account for maintained statements. Total identifies the total number of statements that fall into the respective category across all amendments for each state; mean and St. Dev. represent the mean and standard deviation for the change observed in each amendment.

Table A3. Examples of constitutive syntactic elements.

Constitutive Elements	Example #1 (Arkansas 2001)	Example #2 (Illinois 2021)
Constituted Entity	“Electric utility”	“eligible customer”
Modal
Constitutive Function	means	means
Constituting Properties	a public or investor-owned utility, an electric cooperative, municipal utility, or any private power supplier or marketer that is engaged in the business of supplying electric energy to the ultimate consumer or any customer classes within the state	a retail customer that owns, hosts, or operates, including any third-party owned systems, a solar, wind, or other eligible renewable electrical generating facility.
Activation Condition
Execution Constraint		As used in this Section,

Table A4. Examples of regulative syntactic elements.

Regulative Elements	Example #1 (Virginia 2007)	Example #2 (California 2011)
Attributes	The default service provider	(c)(1) Every electric utility
Deontic	[shall]	shall a standard contract or tariff providing for net energy metering
Aim	purchase	develop
Direct Object	excess electricity	a standard contract or tariff providing for net energy metering
Indirect Object
Activation Conditions
Execution Constraint	at the rate that is provided for such purchases in a net metering standard contract or tariff approved by the Commission, unless the parties agree to a higher rate.