The document discusses UL 1741, a standard for distributed generation systems. It notes that UL 1741 certified systems allow recovery of up to 40% of energy used in beam pumps through regenerative drives. The standard ensures inverters meet requirements for interconnection, safety, output quality and anti-islanding. An Enersaver Power system is highlighted as the first and only drive system compliant with UL 1741, allowing benefits like electricity cost savings, clean power generation, and participation in demand response programs.

1. Presentation to Artificial Lift Forum
November 2011
UL 1741 Distributed Generation Standard
Ronald A. Dombrowski,
Vice President, CCW

2. What is UL1741 and why should I care?

3. UL 1741 is the standard that inverter-based
generators must meet to put electricity on the
grid…
…and get paid for it.

4. You should care about UL1741 because up to
40% of the energy you are putting into your
beam pumps may be recovered with a
regenerative drive system.
With a UL 1741 certified system, that can come
right off your electric bill.

5. You should care about UL1741 because up to
40% of the energy you are putting into your
beam pumps may be recovered with a
regenerative drive system.
With a UL 1741 certified system, that can come
right off your electric bill.

6. Distributed Generation in TEXAS
• Distributed Generation:
An electrical generating facility located at a
customer's point of delivery (point of common
coupling) of ten megawatts (MW) or less and
connected at a voltage less than 60 kilovolts (kV)
which may be connected in parallel operation to
the utility system.

7. Distributed Generation in TEXAS (con’t)
• The Public Utility Commission of Texas (PUCT)
encourages the use of distributed resources.
• Texas Public Utility Regulatory Act (PURA) of
1999 includes customer rights and safeguards
• Section 39.101(b)(3) of PURA states “A
customer is entitled to have access . . . to on-site
distributed generation . . .”

8. Distributed Generation in TEXAS (con’t)
• The PUCT established Substantive Rules for
interconnecting distributed generation.
• Substantive Rules Sections 25.211 and 25.212 address:
– Technical Aspects
– Procedural Aspects
for interconnection of distributed generation.

9. Distributed Generation in TEXAS (con’t)
• The PUCT established Safety Requirements for
interconnecting distributed generation.
• Safety Requirements ensure DG is designed and
installed in a way that:
– is not a safety hazard to utility personnel, equipment or other
customers
– Does not disturb other customers or degrade quality of
distribution system
– Provides reliable service to DG owner and utility

10. Distributed Generation in TEXAS (con’t)
• UL 1741 forms a part of the Safety Requirements
• Virtually all Texas utilities require compliance with UL
1741 standards

11. Distributed Generation in NEW MEXICO
17.9.568.8 APPLICABLE CODES AND STANDARDS:
B. In order to qualify for any interconnection procedures,
each generating facility generator shall be in
conformance with the following codes and standards
as applicable:
(3) UL 1741 Inverters, converters and controllers for use
in independent power systems or equivalent.
TITLE 17 PUBLIC UTILITIES AND UTILITY SERVICES
CHAPTER 9 ELECTRIC SERVICES
PART 568 INTERCONNECTION OF GENERATING FACILITIES WITH A RATED CAPACITY UP TO AND INCLUDING 10 MW
CONNECTING TO A UTILITY SYSTEM

12. UL 1741
• UL 1741 (Second Edition, January 28, 2010)
incorporates:
– IEEE 1547 – Standard for Interconnecting Distributed Resources
with Electric Power Systems
– IEEE 1547.1 – Standard for Conformance Testing Procedures for
Equipment Interconnecting Distributed Resources.

13. UL 1741
• UL 1741 (2nd Edition) also includes requirements for:
– Construction, materials, wiring, component spacing, etc.
– Protection against risks of injury against persons
– Output characteristics and utility compatibility (includes IEEE
1547)
– Rating, Marking
– Specific Tests for various technologies (PV, Wind, Microturbine,
Fuel Cell Engine, etc.)

14. UL 1741
• The CCW regenerative Enersaver Power II has
been tested and certified compliant with the
requirements of the stringent UL 1741 standard
(2nd Edition).
• This testing has certified the Enersaver Power II
meets the standards for alternative energy,
distributed and grid parallel generation systems.

15. UL 1741
• The Enersaver Power II is the first, and currently
the only drive system which complies with this
important standard.

16. UL 1741 Key Requirements
Harmonic Distortion of less than 5% I-THD
• The measured total harmonic distortion of the current
output from inverters must be below 5%.
• The power coming on to the grid is expected to be clean
and not interfere with the operation of the electric
system.

17. UL 1741 Key Requirements

18. Oilfield Power2<Enersaver>
THD taken with Enersaver -VFD running at 60HZ, snap shot
represents a 20 minute capture.
This is 4.5% THD for Current .. 0.8% THD for Voltage

19. UL 1741 Key Requirements
Anti-Islanding Verification Test
• This standard ensures that the inverter will properly shut
down during a power interruption and isolate itself from
the electric grid.
• This standard is of utmost importance to electric
distribution companies as it relates to safety for their
workers.

20. UL 1741 Key Requirements
Frequency variation test
• The inverter must pass a series of simulated tests to
adjust to the frequency of the grid AC power within
specified time standards.

21. UL 1741 Key Requirements
Line/Grid Synchronization Tests
• The inverter system must be able to automatically
synchronize to the grid under many different conditions.

22. UL 1741 Key Requirements
Dielectric Voltage Withstand Test
• The inverter must be able to withstand 1,000 volts plus
twice the rated voltage of the inverter between the input
stage and ground, the output stage and ground, and
between the input and output stages.

23. UL 1741 Key Requirements
Other Tests Performed for UL 1741
Compliance:
• Voltage Variation Output Test
• Component Short Circuit Test
• Loss of Control Circuit Test
• Temperature Withstand Test
• Line/Grid Interactive Test

24. UL 1741 Key Requirements
Other Tests Performed for UL 1741
Compliance:
• Voltage Variation Output Test
• Component Short Circuit Test
• Loss of Control Circuit Test
• Temperature Withstand Test
• Line/Grid Interactive Test

25. UL 1741
• The Enersaver Power II is the first, and currently
the only drive system which complies with this
important standard.

26. Benefits of UL 1741
Compliant Oilfield Drive Systems
• Regenerate Electricity
– for Sale back onto Electric Grid
– Reduce own consumption
• Reduction of energy consumed
• Reduction of demand charges

27. Oilfield Enersaver

28. Benefits of UL 1741
Compliant Oilfield Drive Systems
• Reactive Power (KVARs) go from consuming to
generating
• Generating KVARs:
– Decreases current/amperage required for motor work
– Reduces or eliminates voltage sags
– Significantly decreases KVA demand charges

29. Benefits of UL 1741
Compliant Oilfield Drive Systems
• Clean “Utility Grade” power generated
– Returned to grid for $$ credit
– Benefits other electric devices in area
– active Power (KVARs) go from consuming to
generating
• “GREEN” Carbon Offsetting Power

30. Benefits of UL 1741
Compliant Oilfield Drive Systems
• Increased safety of workers and public
• Opportunities to participate in demand
reduction/demand response programs
• Provides greater energy efficiency

31. Benefits of UL 1741
Compliant Oilfield Drive Systems
QUESTIONS?