It was a busy 2022 for the electricity sector and more of the same is expected heading into 2023. But despite the sector being at the leading edge of the energy revolution, the question on almost everyone's lips in recent weeks has been how many reindeer does it take to power Christmas?
For those who still believe in Santa (which is everyone, obviously, nothing to see here kids), the simple answer is nine. But Transpower Principal Market Advisor Ramu Naidoo has looked beyond Rudolph and his pals to get a handle on how many reindeer would have been needed to power the country at Chrissy if all of our generators had taken a well-earned break.
As Ramu explains, we estimate that the average reindeer can produce about 25% of the power we'd get from an average draught horse, or around 190W (see below for the maths). With the generation requirements on a typical winter's day in New Zealand reaching around 6500 MW, that would require 34 million reindeer hooked up to the grid to keep the lights on and our houses warm (although a harsh winter peak could see the reindeer-wrangler reaching for his whistle to call up an extra four million for support).
The good news for our immigrant caribou workers is that a typical summer's day requires much less electricity, and around 27 million reindeer could take it in their stride. As the following graph shows, they will be busy most of the day with electricity usage fairly consistent from 7am until around six at night.
On the weekend, many would be able to take the day off with up to 25 million reindeer needed in harness.
While on Christmas day the morning load increase between 6am to 9am is greater than the average summer weekend, most of our reindeer helpers would get some time off after the morning peak as load falls away quite quickly with many Kiwi families turning to the barbecue to cook their turkeys and other festive treats, or pulling up stumps entirely to head to the beach.
By 2pm, just 20 million reindeer would be needed to pull away at the pumps to keep the holiday mood cheery.
Ramu acknowledged that it is a big ask to expect 38 million reindeer to travel to New Zealand to help keep the lights on in a cold winter night, not only because they'd be exhausted by the time they got here but also because the global reindeer population is only about 7 million.
However, given their magical powers and the possibility of miracles at Christmas, Ramu's expert advice is that reindeers could be seriously considered for lending a helping hand next Christmas, even if the numbers are stacked against them (see other scientific realities reindeer are up against here).
Calculating reindeer output: This is based on the average rate of work of a draught horse over a day which equates to 1 mechanical horsepower = ~746W (or 746 Joules per second). Using available data of the draught capability of different animals compared to weight we determined a relationship between these two parameters which was used to estimate the expected power capability of the average reindeer given an average reindeer weight of 125kg. This provided the estimated power capability of the average reindeer being ~25% of 1 mechanical horsepower or ~190W.