Electricity
Our annual (KwH) electricity consumption (see graph) fell steadily as a result of the early initiatives and dropped to 38% below its 2005 peak by 2010. The figures shown include an appliance in the business workshop which accounts for the night units ( 35% of total units used). The "Day units" are the domestic units that can be managed by our behaviours and technology. The jump in autumn 2018 is attributable to the arrival of our all electric car. The jump in 2021 and 2022 are a result of the installation of the Air Source Heat Pump.
Air Source Heat Pump (ASHP)
In 2021 we added the biggest step of all by replacing our oil-based central heating and water heating system with an Air Source Heat Pump (ASHP) which significantly ramps up our electricity usage. The move is driven primarily by the environmental need to reduce our heating CO2 footprint and this technolgy fully achieves that. Combined with our sourcing of electricity from Ecotricity (see below) we are assured that only non-nuclear renewables are powering our heating. The very large increase in electricity usage cost is being offset by the elimination of heating oil cost.All electric car
In October 2018 we replaced a petrol car for a brand new 2018 Nissan Leaf, all electric vehicle (EV) with zero emissions. A 7Kw charger on the wall in the garage provides timed top ups to the Electric vehicle during off-peak electricity hours typically midnight to 0700. This is sufficient time to fully charge the 40Kw battery and provide a 150 - 175 mileage range for the day ahead. The economics of running the EV are excellent. Our other petrol based car would cost about 14pence a mile to run. The EV in its first year averaged 2.3 pence per mile. No road tax. Lower servicing costs(as there is no engine.Electricity Supplier - ECOTRICITY
As at Spring 2020 all our household and EV electricity is powered by ECOTRICITY on their "EV Tariff". As with all the company's energy it is100% wind, solar and hydro renewable, part of which is generated by their own onshore wind turbines.The Ecotricity "Fuel Mix Declaration" (FMD) and green credentials in one simple pie chart. Offshore wind 84.9% Onshore wind 14.94% Solar 0.12% Hydro 0.03%
So the electricity we use for our home and electric car has zero carbon emissions in its generation. That ensures a big reduction in our overall carbon footprint.
How much of my electricity supplier's energy is renewable? Download the PDF.
Which electricty supplier delivers the lowest carbon Fuel Mix? Electricity.org gives you the latest data.
Electricity saving technologies
- An Air Source Heat Pump (ASHP) is not an electricity saving technology but it does leverage the electrical input by a factor of about 3 to efficiently maintain a constant temperature in the house. The CO2 footprint is the factor being saved here by its implementation in mid-2021.
- With most of the house using energy efficient light bulbs since 2008, in Autumn 2019, we replaced all bulbs and new strip light units into LED units. With the whole property using only LEDs we expect significant lowering of our cost and carbon generation from lighting.
- Partial switch to energy efficient light bulbs in 2007 and switch of the remainder in 2008.
- Purchase and use of the Brennenstuhl PM 230 Electricity Meter
, and subsequently an Energenie Energy Saving Power Meter, monitoring and measuring instruments to determine the power consumption of a connected appliance and the costs of electricity consumed by that appliance. Both meters cost under £20 and measured the Voltage, Amperage, Wattage and time period the appliance was on. They display the totals of each measure then using an inbuilt tariff option or a spreadsheet, the Kilowatt Hours used and the total cost are calculated. Monthly and annual expenditure for the appliance can be extrapolated. Over a period of 2 months in 2006, all household appliances were measured on this device and a spreadsheet compiled.
View a sample of some appliances monitored.
The largest energy using appliances at that time were identified as:
- the fridge,
- the freezer,
- two computer clusters (PC, Printer, Router, speakers)
- one TV Cluster (TV, DVD, Video)
- the Kettle
and appropriate changes made accordingly.
- More energy-efficient Kettle, Washing machine, Personal Computer, TVs, Freezer and Fridge appliances were installed between 2006 and 2012. Details...
- The same equipment was monitored in the same way 6 years later in 2012 to compare energy consumption in the two years. The table below shows the annual energy consumption (KwH) to run these appliances in 2012 was 41% less than in 2006. Despite the 34% increase in the cost of electricity per unit over the same period, the cost of running these appliances in 2012 was still 35% LESS than in 2006.
- A single power strip was applied to each TV and Computer "cluster" so all appliances switch off/on with the single switch. The habit of powering it all off at the end of a session had to be learned, but has reduced energy consumption. This unit has now been replaced with a EnerGenie power strip which switches off all attached peripherals when the computer is powered down.
Our Electricity saving habits
- Switch off TV and Computer "clusters" at the end of the session or at worst at the end of the day or evening.
- Switch off all appliances at the plug to avoid 'standby' power usage, especially rechargers.
- Minimal use of the electric oven for cooking.
- Switch off lights in rooms not in use.
- Live without high energy appliances like Power shower, Tumble Dryer and Plasma screen TV.
- We air dry laundry.