Improving The Efficiency Of Your Home – Series 2: Heating, Cooling, (Hot) Water – Part Seven
One of the ways to slow the advance of climate change is to reduce your personal carbon usage. While we can’t efficiency our way to climate neutrality, we can buy ourselves time by slowing the rate of carbon emissions and conservation, as Negawatts are often the cheapest form of clean energy available (and the least polluting). Also when you have less energy to replace, it’s cheaper to do so (i.e. if you cut your energy use in half, then only half the renewables are needed to make it sustainable).
Our homes can seem like a monolithic entity — they need heat and or cooling, they use water and heated hot water, they consume electricity, and need lighting and plumbing. But the structure plus our actions can alter how much carbon is produced by several orders of magnitude. Two equivalent homes standing side by side could have 5 to 20 times the difference in carbon pollution produced in daily operation. A 100+ year old leaky home with inefficient appliances and high electricity use creating dozens of tons of CO2 a year can stand next to a Passivhaus or Net Zero home, which has very low or even no carbon emissions whatsoever. And there is a huge continuum in between these extremes. Many existing homes that are inefficient can be upgraded to various degrees to reduce their carbon footprints.
This will be a four-part series:
Series One: Insulation And Air Sealing
Series Two: Heating/Cooling And (Hot) Water
Series Three: Plug Loads
Series Four: Building For Net Zero Or Better
The standard disclaimers apply, all advice is for informational purposes only, CleanTechnica is not responsible for any damages caused by inaccurate information or following any information provided, consult professional expertise before making any modifications to your home, all information is subject to change as our knowledge evolves, and the coffee may be hot.
This article series is focused on detached and semi-detached homes, but many of the concepts are applicable to all building types.
Laundry can be efficient or very inefficient. There are 3 main types of washing machines, top load, top load high efficiency, and front load.
Traditional top load is the most inefficient, typically using ~150-300L/load (40-80 gal/load). To determine how much water you’re using if you have this type of machine, read your water meter before and after a load on your typical loads (regular and larger loads if you wash things like comforters and bulky loads). They often have 2-4 water level settings, so use the lowest needed for a given load.
Top load high efficiency is often more miserly on water and gentler on your clothing, typically using ~75-250L/load (20-66 gal/load). Again test your typical loads. These types of machines often have the ability to sense the size of the load and adjust the water used to minimize water while maintaining cleanliness. This also means that every load will use a slightly different amount of water based on the weight of the laundry in the machine. Also they often have many settings to choose from, so if you have extra dirt you can use a higher water setting if you found the most efficient setting was not enough, although often the Standard or Eco setting works great.
Front load machines are typically very high efficiency, typically using ~30-100L/load (8-27 gal/load). These machines cause the least wear on your clothes, and have superior cleaning abilities in addition to using the least water since they use vertical tumbling to remove dirt, oils, and stains. But they are the most expensive to purchase and have the least service life (and the most expensive repairs). Also mold complaints are common if you don’t leave the door open between loads, or mold develops inside the soap dispensing systems (using pods can help prevent this problem but adds cost). Yet again determine your water used by reading your meter before and after your typical and largest loads or contact the manufacturer if your considering one of their units.
Electricity use varies by brand and machine type. High Efficiency machines do not necessarily use less electricity, but should use (vastly) less water.
If you are replacing your laundry machine due to end of life or for efficiency then check the rating of different manufacturers for durability, warranty performance (some companies give good warranties, then leave you high and dry when you try to use it), and cleaning performance which is objectively tested by many independent reviewers. Ignore right wing propaganda (due to ideology) saying that efficiency is bad for you and they can subjectively tell high efficiency machines don’t clean your clothes. Gaslighting is no replacement for objective testing.
Endeavor to do fewer loads by wearing clothes longer before washing (within reason) and washing full loads (but not overloading which will mean more wear on the clothes and poor cleaning performance). Also, cold water is all that is needed for clean clothes using modern detergents. Warm or hot water wastes a great deal of energy and will typically not make your clothes any cleaner. In fact, depending on the volume of water used and the energy requirements of the machine, using warm or hot water could more than double the energy needed to wash each load. The energy used to heat the water is often overlooked, but can be substantial when you do the math.
Toilets typically use between 3L and 20L per flush, with older units typically being the least efficient. When higher efficiency models came out, they performed poorly, giving low flow toilets a bad reputation. Since then standards have been developed that physically test performance and give a MAP rating to every toilet, hence the flushing performance has measurably improved. Check reviews before replacing your toilet.
Many toilets have small print with the water usage per flush rating on them if you examine them carefully, but older units may not. Once again you can check your water meter before and after a flush and fill to determine the water used. It can be worth counting how many times a day the toilet is flushed, this can help determine payback period for replacement.
Dual flush toilets are also available that allow the user to select low flush for fluids and full flush for solids. These are worthwhile.
You can also save water by not flushing after every use, but if you go this route balance it against sanitary considerations and the fact that you will have to clean the toilet with harsh and expensive chemicals far more frequently. Typically you’re best off going with a low flush or dual flush unit instead.
Hand washing may be one of the greatest developments in sanitation (and Covid-19), but collectively it uses a great deal of water. The best way to reduce water use is to wash your hands with less water and only as long as necessary. Low flow aerators (1-2.5GPM, 3.8-9.5LPM) can reduce the water needed per wash, and if you can handle the cold water, not waiting for the water to get hot or finishing with warm water can reduce the wastage from running the tap down the drain until the water warms up. Also, some soaps work better than others at reducing or increasing the amount of water needed. Alcohol-based hand sanitizers can be appropriate in some situations, but it only kills germs (and Covid-19) but does not remove dirt.
Stay tuned until next week for Part Eight – Other Water Uses and Hot Water Heater Types.