Hot water heating

A partial solution for schools’ energy crisis?

No sector is immune to the current cost-of-living crisis; schools included. A recent report found that many schools cannot afford basics like paper and glue, all are grappling with energy costs, and staff redundancies are imminent.

In this blog post, I suggest one partial solution, that may reduce energy costs per school by around ten percent.

In my everyday life, since I have a glass kettle, it is easy to tell when there is a bit of boiling water left over after making a coffee. Every time, I use this drop of water for something — either to sanitise my taps, or to fill my hot water bottle.

And I was thinking, imagine how much water is boiled by kitchen staff in schools, and poured straight down the sink after cooking. School kitchens most likely use industrial size pans for preparation of foods, like this one:

This particular pan holds 98 litres of water. A small hot water bottle holds 0.5 litres of hot water. So, this pan alone could fill 196 small hot water bottles. Primary schools in the UK have an average of 281 pupils. If we were to give each pupil one full hot water bottle, we would require 140 litres of hot water. So, approximately one and a half pans of the size shown above would be sufficient to provide every pupil in the school with a full hot water bottle.

My idea is therefore to save any boiling water produced by the school kitchen during cooking and to use it to provide a full hot water bottle per pupil for the final lesson of class. On average, hot water bottles stay warm for 1–2 hours; this will cover the period from lunch end until home-time. In conjunction, pupils could be encouraged (or required) to wear a poncho for the last one hour of school — this would conserve more of the heat from the hot water bottle, and more of their bodily heat. It might also be a good idea to make hot drinks available during this lesson, for example hot chocolate or hot vimto. And, if not already utilised in the classroom, physical room screens can ensure that you are only trying to conserve warmth within a confined space, rather than allowing heat to dissipate across the whole classroom.

I would suggest that the final lesson of class be a more relaxed time, for example story time, so that children can congregate on cushions or bean-bags with their hot water bottles and ponchos. Obviously, doing sit-down learning tasks that are cognitively demanding would not be suitable under those conditions.

Assuming that this were a safe suggestion, and that children were able to maintain body temperature at 37C, the heating could potentially be switched off 30 minutes to 1 hour prior to school closing. As such, the temperature would not fall drastically, but would get steadily cooler, until home-time is reached.

Would one hour make a difference?

Yes, according to Herefordshire council, space heating accounts for 47% of all energy costs in a typical school.

Also, I was thinking, what if some school kitchens actually don’t use that much hot water in their day-to-day cooking?

Well, this can also be a solution, rather than a problem. Schools could switch to cooking hot foods that rely on quick cooking in boiling water, rather than meals that rely on long cooking times over gas hobs or in the oven.

There are many foods that cook quickly in boiling water, including: vegetables, chicken, hard boiled eggs, pasta, rice.

A more exotic option is poached fruits:

Of course, not all children are overly keen on fruits and vegetables, especially ones could in an unfamiliar way.

To overcome this issue, schools could use food spinner plates, that encourage children to try small samples of many different food types:

And also provide sweet sauces and accompaniments, like syrups, wafers, cream and chocolate sauce.

Clearly, there will need to be sensible precautions to prevent burns or scalds.

(1) Firstly, each hot water bottle would need a suitable cover. And, the cover needs to be lockable, so that children cannot access the uncovered hot water bottle. This can be achieved by punching a hole through the hot water bottle cover and placing a miniature lock. Additionally, the task of filling and emptying the hot water bottles would be entrusted to a member of staff, for example the kitchen staff.

(2) Secondly, the hot water bottles need to be soaked in disinfectant. Water contained in the hot water bottles will not be completely free of debris. After all, the water has been used to cook all manner of items, including fruits and vegetables. Therefore, the hot water bottles would need to be cleaned periodically.

How can schools acquire all the necessary items (hot water bottles and ponchos) without incurring even more expense?

I advise that parents could be approached, by letter, explaining the heating idea, and to request that any children who already have a hot water bottle and/or poncho/blanket at home are allowed to bring this into school. The items could return home each afternoon with the child, so that the parents’ means of saving on energy is not compromised. Most households do already have access to hot water bottles and blankets — for those who do not, schools could purchase supplies. This would likely work out cheaper in the end, since the items ultimately are a means of keeping the heating off for one extra hour per day.

If you would like to discuss school energy savings with Faith, contact: lianne.abrahams@protonmail.com

Related posts:

A number of states penalize young professionals who may have problems repaying out of control student debt. These states crush hopes and careers by revoking the licenses young people spend years of…

A common question I get asked is: “What skill is a significant differentiator for a Data Scientist?” Here are some thoughts in response to this question. In my experience, a strong product sense is…

So you might be in a similar situation I was in a few years ago. You have a boy dog and a girl dog and one day you wanna make cute pups but you’re not ready right now and neither are they. So how can…