Part 2: Questions for you

40. We want to hear your thoughts on the potential benefits and risks of expanding the regulated voltage range, as well as suggestions for how any changes should be implemented if they were to go ahead.

The benefits of changing the voltage range

41. Increasing distributed generation and changing consumption patterns is challenging the traditional approach to network voltage management. Expanding the permitted voltage range has been proposed as a more cost-effective way to help low voltage networks support more solar PVs than reconfiguring or installing additional network resources.

Q1. Would expanding the upper voltage limit from +6% to +10% help networks host more distributed generation like solar PV? Do you think this is likely to be more, less, or similar in cost to other options, like reconfiguring networks or installing additional infrastructure?

Q2. Would expanding the lower voltage limit from -6% to -10% help networks host more distributed energy resources like electric vehicles? Do you think this likely to be more, less, or similar in cost to other options, like reconfiguring networks or installing additional infrastructure? 

Q3. Beyond costs, do you think expanding the voltage range will have any wider benefits to the security or sustainability of the electricity system?

Q4. Are there any other benefits to expanding the voltage range that have not been mentioned?

The risks of changing the voltage range

Current voltage settings may have a lower risk of causing appliances to fail earlier

42. Appliances are designed and optimised for a certain input voltage. It is possible that supply voltage above design limits can cause appliances to run too fast and too high, accelerating the speed that they depreciate. Similarly, lights can flicker, and motor-based appliances can malfunction if operated below the voltages they were designed for.

43. We are not aware of any evidence that expanding the voltage range in Australia resulted in noticeably more appliance failures and it is likely that most appliances sold in New Zealand can tolerate a greater range of ± 10%, especially products sold internationally. However, we are interested in any evidence of the risks to appliances, so we can properly assess the cost and safety risks any changes may pose to households or businesses.

The risks may be higher for some appliances

44. The failure of some household appliances, especially low value items or products with safety features, may have a limited impact. However, the failure of some more specialised appliances, such as medical equipment, heating systems or devices used to operate essential services, could pose a greater risk to the lives of New Zealanders.

45. It is possible that the age of appliances may be a significant factor. Many modern appliances are designed and tested for a wider range of voltages, especially if they come from or might be exported to, countries that already allow a wider range of voltages. Alternatively, devices that have a long life, for example old water pumps, may be a greater risk from voltage variations.

Q5. Do you have reason to believe that any appliances you manufacture, sell, or use would be at significant risk of failing if the maximum permitted voltage increased from 244 V to 253 V? If so, what appliance(s), why do you think it could be affected, and what would the impact be?

Q6. Do you have reason to believe that any appliances you manufacture, sell, or use would be significantly affected if the minimum voltage was allowed to fall from 216 V to 207 V? If so, what appliance(s), why do you think it could be affected, and what would the impact be?
 
Q7. Are there any specialised appliances that are at higher risk of failing from wider standard voltage ranges, or where the impacts of failures would be particularly serious? 

Q8. Do you think an alternative approach should be taken to manage the demands of distributed energy resources on low voltage networks? If so, what approach and why would it be preferential to expanding voltage limits?

How changes to voltage regulations should be implemented

Introducing changes to voltage regulations safely

46. A phased approach to expanding voltage limits (for example beginning with specific network areas) could be considered if uncertainty remained about their potential impact. Even if the likelihood of appliance failures is low, there may be specific considerations needed to protect appliances where the potential safety implications of a failure are more severe, such as hospital or home medical equipment.

Q9. If voltage limits were expanded, do you believe those changes should be phased in? If so, how? If not, why do you think a phased approach is undesirable? 

Q10. If voltage limits were expanded, are there any specific safeguards you believe should be introduced for ‘higher-risk’ appliances, if any?

The potential costs of expanding the voltage range

47. It is likely that the costs of expanding the voltage range will be small or negligible, beyond the policy work required to update regulations and potentially one-off work by networks to update transformers settings to use the wider permitted range. However, we are interested in knowing about any other costs you consider might be involved and who they may fall on.

Q11. What costs would be involved in expanding the regulated voltage range? Who would face those costs?

Are there other regulations that would need updating?

48. We are aware that altering the permitted voltage ranges may have knock-on impacts to other regulations, or standards incorporated in regulations, such as the AS/NZS 4777 standards on grid connection of energy systems via inverters. Various standards are used for appliances and fittings in New Zealand. A more complete list is available in Schedule 4 of the Electricity (Safety) Regulations 2010.

Q12. Are there other regulations or standards that would need updating if regulated voltage ranges were changed? Please be specific where possible.    

Any further information

Q13. Is there anything which has not been covered by the previous questions that you believe we should consider?