Allan Hansen has been donating blood once a fortnight, since 1991.
He says at first he donated whole blood every three months.
Then he donated whole platelets, the clotting agent in the blood, which took a lot longer.
Last week Hansen was back at the Blood Donor Centre to donate plasma.
He felt fine, he said, looking comfortable on the bed during the 60-minute donation.
"Over the years I have felt part of the family," says Hansen.
He has taken part in the Christmas Parade and other celebrations, as a way of giving back to the Blood Group, he said.
Donor relationship coordinator Sue Rule says they are lucky in Palmerston North with donors, but the demand for plasma is increasing and donor numbers need to double by 2022.
"Plasma demand is increasing 12 per cent year on year.
"The need for plasma donations increased by 45 per cent between 2015 and 2019."
It is estimated that in the next two years New Zealand will need to collect a lot more than 100,000 plasma donations every year.
There are 10,000 plasma donors and another 8000 are needed by June 2022.
Rule says plasma donors are asked to give more than six times a year.
Plasma is the gold-coloured liquid that makes up half our blood, and is used for an ever-increasing number of conditions: autoimmune disorders, accident and trauma patients, boosting the immune systems of people with low antibody levels and providing special clotting factor concentrates for people with bleeding disorders.
Plasma donors can donate up to every two weeks as opposed to every three months because the red blood cells are returned to the body. How is plasma collected?
Blood is temporarily taken from the vein and put through a machine that separates the plasma before returning the red blood cells to the donor.
The process takes around 90 minutes and collects up to three times the usual volume of plasma than can be removed in a single whole blood donation.
Is plasma collected by blood type?
AB blood type is the universal blood type for plasma and can be given to anyone.
People with AB positive, AB negative, B-positive and B-negative make up 15 per cent of the New Zealand population and are encouraged to donate plasma.
O-negative blood types are asked to donate blood as it is the universal blood type for red blood cells.
More plasma is needed because of the increased need to immunoglobulin products, which are natural proteins present in the blood that are essential for stopping infection.
Donating plasma: Contact New Zealand Blood Donor centres to find out if you are eligible to donate.
To become a donor you must meet plasma eligibility criteria which includes, height and weight and having good veins.