When you think of experimentation, what do you think of? Do think of your old school science lessons and Bunsen burners with some beardy science teacher with bad breath, banging on about the periodic table?
When we were kids, experimentation was fun and exciting. We did not know what the outcome would be but at least back then we were excited to find out
So what has happened to us? Have we grown up so much we have lost our adventurous spirit and desire to experiment? Writing this now, I cannot help but ask the question. When did you last run an experiment at work? I suspect being afraid of proving ourselves wrong or stepping outside of our comfort zones are massive drivers for this lack of action.
“When did you last run an Experiment at work?”
Being someone who has run multiple experiments, I can’t understand why more people are not passionate about experimentation. I remember undertaking an Energy audit of a swimming pool and finding that the variable speed drives on the Air Handling units (AHU) for the swimming pool were running at 90% (day) and 80% (night). I suspect these speeds are standard practice across most swimming pools.
The benefit of running your fans at slower speeds lie in the energy savings generated. A 10% reduction in speed generates a 27% reduction in energy saved. This is cube law proven science. The image below shows a 20% reduction in speed generating a 49% reduction in energy.
This is nothing knew and is well known. However, I have not come across many people experimenting with their fan speeds. Surely, in order to get to optimum efficiency we need to be challenging absolutely everything we do? With this in mind, I decided to run an experiment on that swimming pool. I wanted to see how far I could go in slowing down the fan speeds.
Surely, we need to be challenging absolutely everything we do?
So armed up with my laptop I spent a couple of days in the pool spectator area. I quickly realised that the day setting of 90% speed was far too high for most pool sessions.
The pool sessions/bookings varied greatly. We had general swims that could mean 200 people splashing about in the pool. Whilst, at the other end of the scale we had school swimming lessons containing 20 people and sometimes they failed to turn up. I decided to programme the fan speed to the pool programme. With all sessions other than the general swims set at lower than 90% speed..
This seemed to work and did result in some significant energy savings. I even introduced a new fan speed called “Fans Off” which ran between 10pm and 4am. Yes that is right for 6 hours (25% of the time) the fans now consumed no energy whatsoever.
“Time to give it the big en”
However, I was still left unsatisfied by the missed opportunity of a school swimming group not turning up. Situations like this represented an opportunity to rinse further energy savings.
Surely, there was a better, automated way of doing this?
Following consultation with my BMS maintenance supplier, we realised the solution lay in installing air quality and Co2 sensors into the pool hall. The sensors would then control the fan speed. This way when a school failed to show up or a class was cancelled. The sensors would detect this and ramp the fan speed down.
Looking at the data (see earlier Blog on “The Importance of Data Visibility) I could see that during lane swims the fans were never above 60% speed. After school, swimming lessons were another big winner where fans ran at 50% speed. The AHU fans were sized at 12kw so the energy reduction was clearly visible in the data.
The example I have given is one of the best experiments I have conducted to date. The utilisation of air quality sensors was an elegant and effective solution. Consultation with our BMS maintenance supplier was invaluable and although it would be unprofessional to mention their name I will say….
“Tony, I am forever in your debt buddy”
Thinking back about this some years on I realise how much I enjoyed running experiments, we ran 6 experiments in our first year alone. I shall feature others in future blogs. If my memory is correct, I think the costs attached to that experiment were around £200 to wire in the air quality sensors. The energy savings far outweighed this.
If you are not experimenting, how do you know you are running at the most efficient level?
The lesson I learned was that if you are not experimenting with your plant and equipment how do you know you are running at the most efficient level? This is something I firmly believe and have become immensely passionate about.
I suppose my final thoughts are this. Go away and experiment. As Lemmy famously sang "You win some, lose some, its all the same to me". But, on every occasion you experiment you will learn and gain an understanding of how to become more efficient
They say “Nothing ventured, nothing gained” if innovation is to be the currency of the future then experimentation has to be the trading floor for innovation.
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