Föreläsning 9 Energy, Materials

Question 1

What is the consumption of energy in built environment? And what do we need to do to reach the near zero or natural energy goals?

Answer 1

The consumption is really high:
– Buildings (30 to 40%)
– Urban Zones > 50 %

To reach the energy goals we need to:
1. Use sustainable energy (abandoning of nuclear energy)
2. Energy saving (passive houses, power saving, low energy construction)
3. Renewable Energy Sources (solar energy, biomass, wind-power, hydro-power)
4. Efficient Technologies (long and short-distance energy, power-heat coupling)

Question 2

What is the problem with todays energy consumption?

Answer 2

• Fossil Fuel Dependency: Reliance on fossil fuels for energy production leads to air and water pollution, habitat destruction, and greenhouse gas emissions.
• Too high consumption: Unsustainable levels of energy consumption, driven by population growth, urbanization, industrialization, and consumerism, strain natural resources, ecosystems, and the climate system.
• Renewable energy price: The perceived high upfront costs of renewable energy technologies, coupled with the subsidies and incentives provided to fossil fuels, hinder the transition to clean and sustainable energy sources.
  And challenges in scaling up renewable energy production

Question 3

Mention some examples of how we can build houses more energy efficient

Answer 3

With a bioclimatic design trough orientation, envelope, ventilation, daylight, shading, passive solar heating and cooling and choose of windows:

• Orientation and Layout: Positioning buildings to maximize solar exposure for passive heating in colder climates or to minimize solar gain in warmer climates.
• Building Envelope: Designing building envelopes with appropriate insulation, thermal mass, and glazing to regulate heat exchange with the surrounding environment, reduce heat loss or gain, and enhance indoor thermal comfort.
• Natural Ventilation: Incorporating features such as operable windows, vents, and cross-ventilation to reduce the need for mechanical cooling systems.
• Daylighting: Utilizing natural daylight through strategic placement of windows, skylights, and light wells to minimize reliance on artificial lighting.
• Shading and Solar Control: Employing external shading devices, overhangs, louvers, or vegetative screens to mitigate solar heat gain during peak hours while allowing for passive solar heating in cooler seasons.
• Passive Solar Heating and Cooling (HVAC)

Question 4

What is a NZEB (Near Zero Energy Building)?

Answer 4

It refers to a building that has a very high energy performance and low energy consumption. The nearly zero or very low amount of energy required should be covered to a very significant extent by renewable sources, including energy generated on-site or nearby. The concept is a significant step towards achieving energy efficiency and sustainability in the built environment.

Question 5

What strategies can we use to create a more sustainable material consumption?

Answer 5

• Resource Efficiency: Promotes recycling, reusing, and waste reduction to minimize resource depletion and environmental harm.
• Waste Management: Focuses on waste reduction, recycling, and proper disposal to prevent pollution and protect human health and the environment.
• Circular Economy: Encourages the reuse, remanufacturing, and recycling of materials to minimize waste generation and environmental impacts.

Question 6

What is raw material and secondary material?

Answer 6

• Raw material or
  primary material (are
  extracted from nature)
• Secondary materials
  (have already been
  used, for example can
  be recycled materials)

Question 7

What is Solid Waste

Answer 7

Substances or objects that people,
industry and services do not use anymore, and want or need or have the obligation to be disposed off. Example: water bottles, batteries, paper

Classification:
- Domestic
* Organic
* Inorganic
– Industrial
– Hospital

Question 8

Mention some treatment and final disposal methods for waste

Answer 8

1. Transfer Stations: Temporarily store waste before transport.
2. Landfills: Final disposal sites for solid waste.
3. Incineration: Burns waste at high temperatures.
4. Composting: Decomposes organic waste into compost.
5. Anaerobic Digestion: Breaks down organic waste to produce biogas. BIOGAS can be used to supply municipal gas
   networks, can be burned to produce energy or heat facilities

Question 9

What are the impacts and mitigation measures of waste production?

Answer 9

Impacts: The primary direct impact of waste production is the strain on waste management systems. This becomes relevant when waste overwhelms existing disposal systems, potentially reducing the lifespan of landfills, for example. Visual impacts, such as temporary waste storage at construction sites or quarries, are also direct consequences. Indirect impacts include air pollution, noise, and road safety concerns during waste transportation. Risks associated with waste storage or transport, such as air and water contamination or ecological and human health effects, are also significant indirect impacts.

Mitigation measures:
* Technical solutions– act on the production source: reduce waste
production, increase reutilization and recycling
* Minimize the risk of contamination of air, water, soil in waste
management operations
* Integration or recuperation
* Work on the landscape to minimize deposition of waste
* Improve workers’ and users’ awareness for procedures that
minimize the impacts of waste and promote reduction, reutilization
and recycling

Question 10

What are the five steps in the waste policy hierarchy?

Answer 10

Prevention, reuse, recycling, energy recovery and lastly disposal