Energy cost reduction Phase 1 complete!

I have been engaged in a multi year energy cost reduction programme.


Reduce costs of energy as I approach retirement. I want to be able to afford heating and using electricity in the home.

Must be achieved without impacting family (I have no desire to become my dad! “Turn off the lights, shut the door” etc)

There are multiple phases to this.

Phase 1 Reduce consumption - the cheapest energy is energy not used.

Phase 2 Offset energy usage, ie capture cheap rate overnight electricity

Phase 3 Move to an Electric Vehicle

Phase 4 Super insulate the house

Phase 5 Generate own energy

Phase 6 Update heating energy system

Phase 1 is now complete having consistently reduced electricity consumption by 50%.

It was bad, really bad using over 30 kWh per day in Dec 2020, now down to 16 kWh per day.

This has been achieved by, migrating three computers from intel to M1 machines.

Updating washing machine, dryer, freezers to more energy efficient models.

Significant usage of home automation, including making 90% of house lighting automated, motion sensors, link usage (if tv is on and it is below a level of luminance then turn on lighting).

Using HA to monitor anything that could be a heavy user of elec or a smaller user but does it 24x7. Using zwave switches to only turn them on when needed, ie powered a lot of stuff off after Goodnight had been called and powered back when 2 out 3 motion sensors detect movement in the morning.

Also, set all devices in unused rooms to turn off when not in use, guest rooms/ guest bathrooms etc.

So now all ready for Phase 2 and 3 to start In a month or so.


Phase 2 is about putting in three 8.2kWh batteries and charging them overnight and then using them over the next 20 hours.

At today's rates it will achieve an ROI in less than 5 years.

Energy costs are going up in April and Russia's invasion of Ukraine will have a massive impact pushing it up even more.

So I expect a more rapid ROI.

I jumped into Phase 3 early, an EV because it unlocks cheap rate energy so as it is capital neutral and reduces OPEX by about £2,000 a year it became a no brainer.

As an aside over the last two years been developing my central heating and hot water systems, currently on v4 and now working on v5 of the next house so that the heating system will also manage humidity in the house too.

Very very difficult to measure benefits of a 'smart' heating system over the bog standard heating because you can't easily do a side by side comparison - too many daily variables.

But having made every room in the house a 'zone' with independent controls will have had an impact to the bottom line I have no doubt.

Under the smart heating system I can now manage rooms by their usage, ie Lounge and Kitchen need to be about 20.5c, the bedroom 18c, ensuite - well I leave that unmanaged - ie anytime anywhere in the house calls for heat the Ensuite also gets heating.

All unused rooms, ie no one is sat in there for any time they drop to 16c, as do living areas, if any 2 of three motion sensors on the landing detect movement the the house rolls over to Morning mode and the heating kicks in and heats up living areas.

Some lessons learned.

Autonomous task hubs are the way to go. Massively insulates house occupants from outages. ie I have a Hue Hub for all upstairs lighting, another for downstairs.

I am using another Home Automation hub running on a M1 Mac mini Server will run v5 of the Heating and Hot Water as well as Energy management.

The Hubitat hubs will manage all the zigbee devices.

With Node Red in a container in the M1 Mac mini Server providing oversight and exception management - ie if heating parameters are exceeded etc.

This way 90% of lighting is totally autonomous and is 100% solid and reliable.

The heating will be the same, isolated.

The M1 Mac mini runs on a large UPS and the M1 uses so little power it will keep it going for a very long time, the home networking also on UPS so I will be able to receive notifications of any issues as detected by the Nod Red.


I am 73 and have gone through the same while trying to also improve self-reliance. I did everything you have done and now have a base (i.e., spring time) use of about 7 KWh per day. (base is w/o heat or AC usage). I have already addes Solar Panels and a Power Wall to your list.
Some items for consideration:

Smart Thermostats. They do help a lot in reducing energy while maintaining comfort

Home Energy Assessment. This would be a great next step. Have an assessment done by a professional (some utilities provide this service for free). The assessment will make recommendations in you installation to reduce energy usage.

AC maintenance. It is critical to have your AC checked every year (six months for a heat pump). Even a small reduction in the amount of refrigerant can have a large increase in utilization. (They are NOT supposed to leak; however, they sometimes do.)

Solar Panels. Still expensive, but good for 25 years. They fix your cost per KWh, but base size on your six lowest use months average (a lot of advice floating around here - do your research and ask your utility company). (Do not forget capacity addition for an Electric Vehicle.)

Water Management. Not electric, but... Unless your are on a well, this is important. Smart Sprinklers and water flow detectors (to detect leaks and unintended usage) will help reduce your water bill. It may also help your sewer bill which is often based on usage during non-irrigation months.

EDIT: For a project, it would be nice to investigate a remote control for the external air exchange of the heat/AC system. The exchanges are built into newer systems to avoid "sick" houses; however, they usually have 5 levels. The more open, the higher the costs, too closed may (depending on house tightness) may cause humidity / house pollutant problems.

I’m curious if you’re able to distinguish what your highest users of electricity were? Or which components achieved the largest scale reduction by automating?

I have a z-wave energy monitor on the main breaker panel of my house. I can see my total energy usage, but that’s all. I know there are options that can tell me more about each circuit’s energy usage, but I’ll have to install more clamps in the breaker panel to get those more granular readings.

I recently put in Tesla solar panels (14.45 kWh system) and 2 Powerwall+s. Now that I can "see" the electricity usage (I'm grabbing the data from the Powerwalls every 5 minutes), it is somewhat clear as to what is using the most electricity. My biggest "consumers" are - Pool equipment (particularly when freeze guard kicks in and the darn thing runs all night long), dryer and oven. Haven't had the AC kick in as yet, but that is probably going to be the highest.

I've done some of the things you have mentioned - all bulbs are LED, lighting is motion driven (at least in the areas where people "forget" to turn of the lights), but I don't see a huge draw from that.

For the first 3 days of March, we ran entirely off-grid using solar and battery. Three good solar days and it was warm, so the battery was able to run the house overnight.

I do think we need to get a home energy assessment - anyone got recommendations? I am in the DFW area (Texas)

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I do not have the equipment for that type of energy monitoring. However, they make equipment that can do that (just why). I did look at my daily (15 minute) energy consumption from the Utility company to help determine sizing. In that I can see when I cook meals (large jump) or watch TV (smaller - steady jump). So -

  • Concentrate on energy saving kitchen appliances. Look for performance, not just Energy Star rating.
  • Appliances. Watch out for energy leaks from some appliances (you can check with a single EM plug monitor when the appliance is off for a while, to determine if you should use a smart plug). This includes rarely used wifi-printers.
  • TV's (by the amount of time we use them) - get the lowest consumption. Bigger is better for "entertainment" - but it costs. My 60", 2020 Samsung uses 80 watts plus another 20 watts for the Fire TV Cube per hour.
  • Alexa, Google Home. Consider putting behind smart switch to turn off during non-use periods (unless you use them as poor-man's buglar detectors).
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I live in Frisco and am on Co-Serve. My first assessment would be to check if my power company provides the service (Co-Serve used to do this for free). They will look at your usages and setups. One neighbor was told to reduce the fresh air exchange.

For water, the City may provide a free sprinkler assessment, providing recommended settings and verify the operation of the system.

(When I lived in Austin, the utility did this. The checked and provided a list of remediations and provided a grant for some of the costs.)


My provider is Oncor (Dallas area) so will check with them. Thanks!

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My average annual consumption used to be around 15000 kWh. Starting in 2016, I gradually reduced it to just under 10000 kWh per year (so about a 30% reduction).

I'm redoing the exterior insulation this year, so I hope to drop this a little further.

Home automation turned out to be one my major saving methods. I stopped cooling my house during the summer based on indoor temperature. Rather, it is controlled based on the indoor dew point. This has resulted in fewer, but longer, cycle times, and the home also feels much better.


I think Oncor is the line provider. Your service provider would be a separate company (TXU, Reliant) who you pay your bill through.

You can also get commercial audits - but be careful - these can be sales calls.

Very interesting concept. What do you use as decision parameters for cooling? Dew Point only or some combination of Temperature/Dew Point? Definitely something for a smart app consideration.

(I live in Texas, USA - high AC utilization from June through September.)

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Solely dew-point in cooling mode. Solely temperature in heating mode.

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What I found were high energy users - either peak or over time

Washing Machine

2011 iMac i7 Plex Server with 3 x Drobos - using 3.5kWh per day alone!! replaced with M1 Mac mini with three external HDDs (12tb/12tb/18tb) daily usage now 300W per day

Plex Server runs Sonos, Node Red, Indigo, does all DVD ripping, 4 HD Channel DVR

I have taken the Unify 16 Switch 150W out as well - will put it back when I have the new house - it was a heavy energy user.

The 65" UHD is a heavy user - so if one person is sat in the lounge I encourage them to watch using their iPad :slight_smile: TV also uses multiple Sonos devices so adds to power usage.

We have a 32" tv with an AppleTV on it that plays an App with an HD fire running it sits in the fireplace and it makes the lounge feel much warmer - along with fire crackling noises - he it makes my wife happy!!!

My Office 43" 4k monitor is also pretty heavy - but I need to work and it is the only monitor I use for multiple computers.

For Home Automation I and using a range of things.

I have energy monitors on the Fridge, and two freezers - also alarmed if they go over/under temp but also if the go over under energy use - the Fridge uses about 350w per day, the freezers about 700w per day. When we move we will use a smaller fridge/freezer in the kitchen and the freezers looking at powering them off during the day (unless temp gets too hot, then have them work hard during cheap energy for 4 hours during the night)

The Electric Oven is massive user, now use an Air Fryer to do baking, cooking in - high kW user but for a MUCH shorter period.

Also replaced kettle with a device that only boils exact amounts of water - ie a teapot uses exactly 500ml, so now we only bill exactly what we need, much quicker too.

Then I did a power saving HA thing.

Used largely zigbee sockets and powered off Hue/Sonos devices around the house where possible/practical - usually only where I could have multiple devices all sitting on a single multi socket then I could power off a lot of stuff with one switch.

This kicks in 30 mins AFTER Goodnight is called and the house goes into Night mode, turns on internal downstairs cameras, powers everything down etc etc,

Also have a routine called guest mode which shuts down the 4 guest rooms, two bed rooms and two bathrooms, just shuts everything down and sets heating to 16c, when Guest Mode enabled powers everything back up and sets rooms to the right temperature.

Also did this for rooms when we don't sit around - Utility/storage rooms.

On the whole been very successful, not sure how I could get down much more while I am still working from home.

In Phase 2 will be able to move kWh from 37.7p to 7.5p reducing my Elec bill by nearly £2,000 per year.

The house we are buying has two large clear south facing roofs which should take a 6kWh and a 4 kWh pvs when we get around to Phase 4, when cheap rate energy hits about 25p kWh.

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Good point!!

At least don't have to worry about AC in the UK - but for the next version of my heating system I will take into account how the house 'feels' ie the humidity level as it has an impact, will look into whether cheaper to turn heat up or run dehumidifiers.


I cannot find a way to do that, not while I am still working from home.

No AC needed in the UK.

I looked long and hard at Solar/Wind and put it on hold.

The house we have just bought has a really good couple of roofs for solar - so ready but more cost effective in the UK to get batteries, for us about 19kWh of daily usage.

With the 4 hours of cheap electricity between midnight and 4am at 7.5p kWh rather than the standard 37.7p kWh current charge.

In April it will go up, again , a lot and with Russia playing up it will keep going up.

Buy all our elec at 7.5p kWh makes the purchase of Solar/Wind cost ineffective.

Have to do all the math but my gut feeling is when Cheap rate Elec goes to ~25p kWh then Solar/Wind are back on the agenda.

In the UK you are metered on water coming in, for every £1 you pay for water you automatically are charged £2 for sewage.

So have been looking at a system that collects rain water from roofs and filters it and put it into a large under ground tank- which is pumped to the roof and feeds WCs and yard taps.

In Phase 4 looking a super insulating the house - external cladding systems and upgraded triple glazed windows.

Will definitely get an Energy Assessment to identify next steps.

I cheat. Gas is separate. In December, I had a $10 gas bill added to that. In Texas, my low months are Oct/Nov/Dec (gas and electric). High are Jul/Aug/Sep (mostly elec - air conditioner). My average bill was below $90 per month in 2021. With solar panels will go down this year.

Not cheating :slight_smile:

Most of the UK use Gas for Central heating and wholesale Gas has increased 50 fold in the last year,

I was paying a year ago 2.4p kWh for gas now I am paying 4.2p and the current rate is 10p and it is looking good to hit 20p per kWh this year.

My new house is oil fired central heating and that used to be expensive but right now is looking much more cost effective.

Yeah - you are right. I just changed companies to MP2 as they have an arrangement with Tesla and net metering.

Interesting - any chance I can pick your brain on how you do this?

Are you plotted values those for 2021 ? Do you have delta values from last year?