When Jack Monroe decided to use Kickstarter to self-publish a third cookbook, the austerity campaigner turned cooking columnist hoped to raise £8,000 – and has instead raised triple that, in less than 24 hours.

The author, columnist and activist launched the Kickstarter campaign at 5pm yesterday, looking for £8,000 to publish a new collection of budget recipes, Cooking on a Bootstrap. “I might not succeed – Kickstarters are only successful if they reach their full funding amount, and I have crunched the numbers to try to keep my costs low to deliver an affordable cookbook, without compromising on the quality,” Monroe wrote to potential backers, offering as incentives everything from a signed copy of the new book for £12, to a five-course dinner cooked at the backer’s house for £2,000.

By lunchtime today, Monroe had raised almost £23,000, and was trying to work out how to manage distribution of the new title.

“I didn’t know if there would be demand for a book three from me – I didn’t know if it would translate to book sales,” Monroe told the Guardian today. “I didn’t feel I was in the right place to be trying to sell myself to big corporations, so this seemed like a nice, gentle way of doing it. I could not have imagined it would do what it has done already. It’s just bonkers … my benchmark was that I might sell 1,000 copies and make a small profit, and that would be nice.”

The book, Monroe added, is “very unlikely to be physically for sale in shops like Tesco and WH Smith, so this is for people to invest in their personal copies”.

Monroe said the extra money raised would go towards printing more copies of the title, which will include 100 budget recipes on themes such as “Breads and Breakfasts, Super Soups, Beans Pulses and Lentils, etc, with extra chapters “Eat Your Greens” and “Don’t Throw That Away” for nifty tips on using leftovers (stale cake truffles, anyone, or bread-crust soup?).

On the Kickstarter pitch, Monroe called the book “an absolute joy to write; irreverent, cheeky, nifty, thrifty and delightful”, saying it would be more simple than their second book, A Year in 120 Recipes. “As beautiful as it was, the glass slipper didn’t quite fit my budget foot, so I’m going back to basics,” they wrote.

Monroe published their first cookbook, the bestselling A Girl Called Jack, with the Penguin imprint Michael Joseph. Laying out how to cook healthy meals on a budget, it draws from the time when Monroe was spending only £10 a week to feed their toddler.

Monroe did not approach any publishers with the third book, partly because they didn’t want to keep readers waiting for the 12-18 months it would take a mainstream publisher to release it.

“I’ve not fallen out with anyone,” Monroe said. “People are asking for it now, so I looked into self-publishing, and it really ignited a fire in me. I tried to talk myself out of it, saying ‘don’t be ridiculous, it’ll be a huge project’. I gave myself four weeks to talk myself in or out of it. I put together a 27-page book proposal, and costed and accounted for every eventuality … It’s going to be hard work, it’s a massive project, but I just feel really compelled to do it.”

Monroe knows the book’s target audience don’t have £2,000 to spend on a five-course dinner cooked by them, “but if someone does, it means I can keep the cover price lower, so that those who don’t have £20 can pay £12 for it. It’s those who can chip in for those who can’t – a sort of cooperative model of publishing.”

Monroe, who writes a column for the Observer, revealed they were transgender in October this year. In a post on their website, they requested that media outlet address them with the pronouns them/they.

• Cooking on a Bootstrap will be published in May.