Tangential to my automation hobby I’ve found that reducing energy usage is another great outlet for creativity – optimisation being the overarching interest, plus there is overlap in automation and energy saving I found. The secondary challenge is for the solutions to not come at the cost of (too much) comfort.
I was under the impression that I had already done quite a decent job on reducing energy consumption in our house, until I got my hands on an EnergyFlip. The EnergyFlip device, along with its app, allowed me to read out our analogue gas meter and power meter real time. And let me tell you, the energy saving lamps we still used in the barn were not doing what their name implies (40+ Watt per lamp!). So those were the first to be replaced by low power LED lighting.
The LED cluster lighting we use at night in the corridor upstairs was also not as energy efficient as I thought, so that got replaced straight away as well plus connected to a Philips Hue smart plug and motion sensor (went from 50W continously at night to 6W intermittently). The rest of the house already used Philips Hue lighting.
Here is a list of all other items that got optimised, divided into their relative utility. Note that water saving features are mainly intended to save on gas by reducing the flow of warm water.
- Optima W TC500 WiFi plugin thermostat floor heating pump switch
- The pump of a floor heating system will run continuously, come summer or winter. And while these pumps have become quite energy efficient, it does not make sense to have them run without purpose.
- The Grundfos Alpha2 L 15-60 pump (5 to 45W) we have is already quite energy efficient, but the pump switch will ensure the pump will only run when the central heating is on. And just to make sure the pump doesn’t get stuck, it will run for a few minutes every day.
- Smeg water kettle with variable temperature
- Next to adjusting the amount of water you boil to the amount you actually require (you’d be amazed how many people fill up their electric kettle all the way every time they just want to make one cup of tea), it’s also possible to dose the energy by adjusting temperature.
- Added benefit is that you always have the perfect temperature for each specific type of tea.
- Stand-by killer TV
- While it is possible to use a standard power strip with on/off switch for the TV, laziness and ease-of-use are determining for effectiveness of using such power saving methods.
- Instead, we’re using a stand-by killer that can be triggered by the remote control of the television. All you need to do is hit the “on” button twice on your remote instead of just once to fire up your television, and when you turn off the tv the stand-by killer will do the rest.
- Standard power strip with on/off switch
- Non-explanatory really, we use this wherever other solutions would not suffice, for example for our microwave and our amplifier. I was surprised how much energy the latter one used in standby mode, and unfortunately stand-by killers did not work for the amplifier.
- Ansmann AES1 energy saving mains socket
- This is a time controlled countdown mains timer, which disconnects attached loads automatically and safe from mains power after the user set operating time.
- We’re using this socket to cut power to products that you do not frequently need to charge but are always plugged in, think of the electric tooth brush or electric razor. When you do want to charge them, just press the button so the device is powered for 4 or 8 hours and you’re done.
- Ecosavers Battery Charger AA+AAA
- Very minor, but all our battery operated devices use rechargeable batteries. Whenever you charge those batteries, the charger will keep using power after the batteries are charged if left plugged in. The Ecosavers battery charger will kill power after the batteries are fully charged.
- Cat water fountain plugged in to a Philips Hue smart plug and triggered by a motion sensor
- Okay I admit this one has gone a bit too far, as these small pumps only use between 1 to 3 Watts, but at some point it just becomes a challenge to reduce baseload as much as possible. And let’s be honest, the investment of the smart plug and motion sensor is one that will never be returned in this application.
- EasyDrain multi WRG energy-saving siphon
- We installed this during renovation, as there is no way to do this retrofit. Our bathroom is on the ground floor, hence we opted for a horizontal heat recovery unit. EasyDrain claims this unit can recover up to 30% of waste water heat.
- Our experience with this siphon has been an absolute nightmare: it clogs so easily. Unclogging it requires a special tool, and during unclogging you ironically waste a fair bit of water and heat. No way to undo this one unfortunately.
- Boiler optimisation
- There are several basic ways to optimise settings of your boiler, and of course plenty more detailed ones. I will only describe the basic ones here.
- Reducing supply temperature of the central heating system. This depends a bit on the type of radiators you have in your house, but we reduced it to about 45-50 degrees Celsius without problem.
- Reducing warm water temperature to 60 degrees Celsius. Lower than that is not recommended due to risk of legionella.
- Changing from comfort mode to eco mode setting on the boiler means you’ll have to wait a bit longer before you receive warm water, as the system does not continuously waste gas to keep your water warm ready at all times.
- Hydronic balancing
- This is the process of optimizing the distribution of water by equalizing the system pressure, with the aim to optimally transfer heat produced by the boiler. There are plenty of guides available online.
- In combination with reducing the supply temperature this measure optimises gas use by a fair bit.
- Speedcomfort radiator fans
- Radiator fans, in combination with hydronic balancing, ensure an optimum heat transfer from radiator to air. Especially with lower central heating temperature, convection no longer is a reliable means of heat transfer.
- One big drawback to radiator fans is the sound. You’ll experience this low white noise, comparable to a fridge running in the background, which can be annoying. The fans are triggered by a thermostat attached to the radiator, so when the room is at the right temperature and the central heating turns off, the fans also stop.
- The big advantage of the radiator fans is how quickly and evenly you heat up a room. It really surprised me how well it works and is very pleasant.
- Neoperl Push aerator
- Aerators come in many different versions, but all work according to a similar method: they mix air into the stream of water to reduce the amount of water required to still give you the experience of a full stream of water. This works for taps, but also for shower heads.
- For the taps, I’ve experimented with the really low flow aerators (~1.3 litres per minute), however these have several issues. One: washing your hands takes impossibly long and becomes annoying to do. Two: try filling up the water kettle with such a low flow!
- In comes the perfect solution: the Neoperl Push aerator. It has two settings: 5 litres per minute in water saving mode or 11 litres per minute at full flow. Just press the button on the aerator to switch between the two modes.
- Neoperl flow controller
- For our style of shower heads, I could not find energy saving variants. Instead, I opted to use retrofit flow controllers by Neoperl.
- These flow controllers provide a constant liter capacity almost independent of the flow pressure. So our very inefficient rain shower head can still be made slightly less wasteful by adding a 10 litres per minute flow controller. The other shower heads are limited to 6 litres per minute.
After all that the resulting baseload is now about 60 Watts; I’ve not discovered any ways (yet) to reduce it any further. One of the downsides of automation is that every system has its own gateway and is always standby, but that is trade-off I’m definitely willing to make.