250 Energy-Saving Measures in Buildings

Today we bring you an article with a slightly different approach. We would like to present a very interesting report that discusses 250 energy-saving measures in buildings.

The report, prepared by the CIRCE group and freely distributed by the Tribe platform, can be downloaded online and, although it is written in English, it is very clear and easily understandable regardless of one’s level of comprehension in that language.

Divided into two parts “short-term measures” and “long-term measures”, the 250 energy-saving measures in buildings are classified according to whether they belong to the building envelope, ventilation/climate control, hot water production, lighting, electricity, and other uses.

Below, we will explain the objectives of this report, which is part of a project funded by various European companies.

Finally, we will summarize the content of the document, emphasizing those more domestic aspects that we can apply immediately as energy-saving measures in buildings.

Authors and Contributors to the Report

TRIBE is an international project funded by the European Union, as well as by private entities or companies*** involved in the world of construction and sustainable building.

These companies are: Circe, Acciona, Zaragoza Vivienda (Spain), Özyeğin University (Turkey), University of Graz (Austria), Deloitte (France), and finally The Interactive Institute (Sweden).

Among all of them, the one responsible for drafting the article and therefore its main author is CIRCE.

250 Energy-Saving Measures in Buildings

The 250 energy-saving measures in buildings focus primarily on five areas: building envelope, heating, hot water, ventilation, lighting, and electricity.

1. Building Envelope

The envelope of a building protects its occupants and plays a very important role in regulating the environment and environmental conditions of the interior.

It is a skin that begins at the base or foundations of the building and rises to the roof in the form of walls with openings (windows and doors). This skin clearly separates the interior from the exterior of the building.

Therefore, it is the part that receives all the impacts and aggressions from the outside and, depending on the characteristics and properties it has, will transfer them to a greater or lesser extent to the interior.

One of the most relevant factors is solar radiation. The envelope receives irradiation throughout the day, due to its constant exposure to the sun. It captures the radiation that flows inward, altering the environmental quality of the interior.

A well-designed envelope ensures the comfort and efficiency of the entire building.

Some of the 250 energy-saving measures in buildings, related to the envelope, are: controlling the insulation of the envelope walls, installing efficient and airtight windows, and improving or ensuring insulation at points at risk of thermal bridges.

2. Heating (HVAC Systems)

The heating or thermal conditioning of a building is normally handled by ventilation and air conditioning systems.

These systems are grouped under the acronym HVAC. This designation, which includes heating, ventilation, and air conditioning, is increasingly used. Therefore, the acronym is understood as: H (heating), V (ventilating), AC (air conditioned).

In many buildings, a great deal of energy is lost by installing non-optimized air conditioning systems.

We consider it very important and an investment that will be amortized over time, the installation of HVAC systems configured under the premises of energy efficiency and that, therefore, minimize the use and consumption of energy.

In addition to energy consumption, these systems have a strong impact on indoor environmental quality (IEQ). Poor design of heating equipment can harm the health of building occupants as well as their comfort.

The measures that can be taken regarding heating systems are: the installation of humidifiers, condensation controllers, and opting for systems such as radiant floor heating to condition the interior of the building.

3. Domestic Hot Water (DHW)

Domestic hot water (DHW) encompasses the volume of water intended for human consumption, that is, potable water, which has also been heated.

It is used for personal consumption, sanitary uses (baths, showers, etc.), and for other cleaning uses (dishwashing, washing machine, dishwasher, floor washing).

Normally, the water comes from the building’s water installation.

At first glance, it may seem that reducing water consumption has nothing to do with any of the 250 energy-saving measures in buildings, but in reality, the key to the matter lies in the fact that this water requires energy to be heated, treated, and pumped.

To reduce consumption, and therefore also the energy investment, we can: opt for the installation of showers instead of bathtubs, choose low-flow showerheads and faucets, water aerators, etc.

Once this step is taken, we can also intervene with measures that seek to eliminate inefficient water heating systems by seeking others whose combustion is completely efficient and losses are avoided. There are closed hot water circuits (with return and reuse of the same) and CO₂ heat pumps, which are two very interesting options to consider among the 250 energy-saving measures in buildings.

4. Lighting

Energy is used both to supply the bulbs themselves and to counteract the thermal variations that artificial lighting may generate within an interior environment.

To address these problems from the beginning of the design process, it is important to determine what type of lighting (both natural and artificial) we will use in our building.

We can consider installing sensors of all types; daylight, motion, temperature, etc., that help us control in a home automation and efficient manner when to use artificial light and when not to.

Likewise, controlling the number of lighting points according to the use of one area or another is something that can save a lot of energy in a building.

We must also not forget small gestures such as turning off the lights when leaving a room or area, but this is something that cannot be controlled in the design process.

5. Electrical Systems

Choosing efficient devices and making appropriate use of them are two actions that will serve to further reduce energy consumption.

In addition, these devices generate heat with their use, increasing the internal load and indirectly influencing the energy demand of the building’s air conditioning.

Among the 250 energy-saving measures in buildings in the article, we can find examples such as: purchasing monitors with LCD screens, installing devices with the Energy Star label, using the screen saver appropriately…

6. Other Measures

This is the section where we will find those measures that cannot be classified in the previous sections.

There will be measures such as “wearing appropriate clothing,” “implementation of a compressed work schedule,” “installation of solar thermal panels,” “installation of ICT systems,” and a long list of others.

Short-Term Energy-Saving Measures in Buildings

Building Envelope

Close windows and doors when HVAC systems are operating:

Simply by ensuring that windows or doors are not opened unnecessarily, especially when heating, cooling, or air conditioning systems are operating, many energy losses through the facades can be avoided.

To ventilate a room, it is sufficient to have the window open for 10 minutes. Doing so for longer implies losing heat from the heating system or cold from the air conditioning system. It is recommended to turn off these systems during the time that indoor air renewal lasts.

Control sun exposure on the exterior facade:

Depending on what time of year we are in, we should block or allow direct solar radiation on the facade and its openings.

In cold seasons, it will be advisable to open the solar filters and allow the entry of both natural light and radiation to increase the thermal load inside.

On the other hand, in hot seasons, we will seek to protect ourselves from solar radiation using filters such as pergolas, louvered windows, awnings, etc., to avoid internal overheating.

HVAC System

Turn off air conditioning systems when rooms are empty:

When leaving a room, even for a short time, the air conditioning should be turned off.

The recommendation also mentions that if possible, the air conditioning should be turned off 20 minutes before leaving, as it will remain comfortable during this time, maximizing the energy investment of the unit.

Adjust the thermostat temperature appropriately:

Each degree that the thermostat is raised above 21°C (recommended reference point for winter) implies an unnecessary waste of energy of up to 6-8%.

While in summer, each degree below 25°C (recommended reference point for summer) implies excessive consumption of around 6-8%.

Domestic Hot Water DHW (Consumption) – DHW Domestic Hot Water

Installation of a timer for the DHW recirculation pump:

It is recommended to install a timer that disconnects the recirculation pump during the hours when there is no demand for DHW in the building.

In this case, in addition to saving energy consumption, we will improve the useful life of our recirculation pump.

Installation of low-flow showerheads:

One of the solutions to save water and energy consists of placing an aerator at the outlet of the showerheads. These devices are screwed onto the outlet of the showerhead, which reduces the water flow.

They are compatible with most showerheads, as they are available in different sizes and different types of threads.

They are easy to install and achieve a pumping energy saving of 50% and hot water production of 30%.

In addition, the use of low-flow showerheads allows for a 50% saving in water consumption.

Lighting

Use adjustable and focusable lighting:

This saving measure proposes the installation of adjustable lighting. That is, a type of lighting that can be focused or dimmed more according to the use required at each moment.

For example, in the case of wanting to read or work, we could focus the light more, and on the other hand, for day-to-day activities, we will not need as much power or light concentration, so the light can be more diffuse and soft.

Turn off lighting in unused rooms or areas:

If there are no presence detectors, the light should be turned off when a room is not in use.

This measure should be especially taken into account in those spaces generally closed during weekends, ensuring that any unnecessary light is turned off.

Other Short-Term Energy-Saving Measures

Use stairs instead of elevators:

For levels below the third floor, it is healthier, more economical, and more ecological to go up and down the stairs than to use the elevator. Below the fifth floor, it is also recommended to walk down the stairs to the street.

Wear appropriate clothing:

Building users can contribute to their own comfort by wearing appropriate clothing according to the time of year.

Long-Term Energy-Saving Measures in Buildings

Building Envelope

Add or increase insulation on the interior part of the facade:

The interior insulation system is based on the placement of thermal insulation in the internal layers of the facades and side walls to then cover with a new interior finish, generally laminated plasterboard or hollow brick cladding.

This system allows for rapid heating of living areas.

Install a green roof:

In addition to contributing to the renewal of oxygen in the atmosphere, vegetation acts as protection against solar radiation in summer, preventing overheating and temperature fluctuation within buildings.

In winter, it would function as organic insulation that prevents internal energy losses.
It is mainly used on flat and slightly sloped roofs.

HVAC System

Installation of a biomass boiler:

These are compact units specifically designed to operate with biomass. All of them have automatic ignition regulation systems and some even have ash removal systems that facilitate handling for the user.

More specifically, biomass boilers designed for pellets* are very efficient and more compact than other biomass boilers due to the characteristics of this fuel: calorific value, compaction, etc.

* Pellets are a completely natural product, classified as solid biomass, which is formed by very small cylinders, a few millimeters in diameter, made from dry natural sawdust.

Installation of radiant floor heating:

The most common type of radiant floor heating uses a network of polyethylene tubes installed under the floor, where hot water will circulate in a temperature range between 34°C and 46°C. Therefore, an interior temperature of between 18 and 22°C is achieved.

It is the ideal option to combine with solar thermal energy or geothermal heat pumps, since the temperature at which the water circulates is around 40°C, while in conventional radiator systems it is necessary to raise it to 60°C or more.

Domestic Hot Water DHW (Consumption) – DHW Domestic Hot Water

Installation of a hot water return circuit:

An action that can be carried out to improve the efficiency of the DHW system consists of installing a hot water return circuit in the distribution network.

These systems maintain the hot water circuit, significantly reducing water and energy losses.

Installation of drain water heat recovery systems (DWHR):

Although it may seem somewhat complicated, drain water heat recovery units consist of tubes coiled around the drain pipes that capture heat from wastewater as it exits the building.

This recovered heat is returned to the hot water system, which reduces the energy required to provide hot water in the building.

Lighting

Installation of light-emitting diode (LED) lamps:

The light in an LED is emitted by a solid object, rather than a gas, as is the case with fluorescent tubes.

The LED is a semiconductor diode that emits light when traversed by an electric current. When the current flows through the diode, energy is released in the form of photons, which is light.

Start-up occurs instantly at 100% of its intensity, without flickering or start-up periods.

In addition, unlike other systems, it does not degrade according to the number of times it is turned on.

Finally, it is a less polluting type of lighting as it does not contain mercury and has greater efficiency in cold environments and can be turned on at low temperatures (down to -40°C).

There are other types of efficient lighting such as halogen or compact fluorescent. The report also discusses them.

Install presence detectors in areas of sporadic use:

There are many types of detectors for light control.

In this case, presence detectors are used to connect or disconnect the lighting of any space according to the presence or absence of people in it.

With this, the control of turning on and off is performed automatically, without forcing anyone to operate it, so a switch will only remain on when it is actually required that the room be illuminated, achieving great energy savings for the entire community.

Other Long-Term Energy-Saving Measures

Installation of solar thermal panels:

The solar thermal energy capture system is a technology that harnesses solar radiation to produce thermal energy, which can then be used as DHW, heating, or to heat swimming pools, among others.

These systems can generate up to 70% of the energy needed in buildings, residential and commercial establishments.

They are a source of green energy, as they do not emit carbon dioxide into the environment, their installation is simple, and they can be easily integrated into existing heating systems.

Install direct traction electric elevators:

These are state-of-the-art elevators, electric and direct traction. The machinery is smaller, thus avoiding reduction elements such as gears, bearings, oils, etc.

This type of elevator represents a significant technological change in terms of energy consumption and energy efficiency. In large buildings, the savings can be up to 20% in energy and 30% in the electricity bill!

It is also worth mentioning that they are quieter. They generate up to ten times less noise than conventional elevators.

At Slow Studio, we particularly appreciate this report for its clarity and for the fact that it largely shares our objectives and way of thinking: always advocating for the energy efficiency of our buildings and homes.

We are available to resolve any questions that may arise and especially if you are considering a sustainable and efficient building project and feel uncertain about how to approach it.