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Passivhaus: maximising comfort while minimising energy



In the late 80s, two building researchers – Bo Adamson of Lund University, Sweden and Wolfgang Feist of Institute for Housing and the Environment, Germany – came up with an idea to maximise the comfort of homes while dramatically reducing their energy usage. The result was the Passivhaus standard, by which over 25,000 properties around the world are now certified .

In the UK, the Passivhaus standard has been promoted and protected by the Passivhaus Trust since 2010. It’s a very new concept, with around 200 complete and certified passive houses currently.

But with over 500 Passivhaus-certified buildings in the pipeline, within two years there is set to be over 1,000 homes with the accreditation.

The Passivhaus Trust’s chief executive Jon Bootland tells Blue & Green Tomorrow more.

This article originally appeared in Blue & Green Tomorrow’s Guide to Sustainable Homes 2013.

Why do we need the Passivhaus standard?

There are consistent problems in the performance of new homes around their energy use, ventilation and potential overheating risks, and therefore the wellbeing of the occupants. Passivhaus, as a low-energy and comfort standard, gives you a software tool and a standard to come up with a solution that addresses all of those things and resolves them all for you.

The Passivhaus Trust promotes the standard in the UK, ensures its integrity, and makes sure that when Passivhaus buildings are built to that standard, they do what they say. It’s a very high quality standard that has a lot of rigour in its approach.

What is a passive house?

It’s a very low-energy building that provides optimal occupant comfort conditions, adjusted for the local environment.

More specifically, it’s a building that can meet all of its heating energy requirements, simply by heating small amounts of ventilation air coming into the building. You need very little heating.

Is the definition of a sustainable home different?

Passivhaus is an energy and comfort standard only. That’s all it does. It does that very well, and very few other people can do that at the minute.

A sustainable home must address lots of other things as well, such as the kind of materials that you use in the home, or whether you’ve got green space nearby, or whether you’re sited near public transport links or local amenities. Passivhaus doesn’t address any of those; it just sorts out very well the energy and comfort parts.

Is the Passivhaus standard for new homes only?

No, there is a Passivhaus standard for retrofit as well. It’s a very exacting standard, so it’s not something to be undertaken lightly. And it is slightly less demanding than the new-build standard, because it needs to take into account things that you can’t change, like the orientation of the building, which affects how much sunlight you’ll gain during winter months for example.

You can’t change that when your house is already built, so we have to make an allowance for that on existing homes. It’s also very difficult to insulate underneath the floor in an existing building, so the standard is relaxed slightly for a refurbishment project, but it is still very demanding.

Can the Passivhaus standard become mainstream?

I’m not sure it’s going to be a product for the mass market house builders for a few years. That’s because the main benefit is in the running costs, which benefit the occupier, not the builder! Heating bills might be £100-£200 per year for a Passivhaus, compared to £1,200-£1,500 a year for a typical home. That’s an enormous difference.

If you’re a private buyer and this is going to be your house for life, and you’re going to be retiring into this house and owning it for 20 years, saving £1,500 a year on your heating bill makes a lot of sense. You’ll have a much higher quality home, it should retain its value better and it should be easier to maintain, so it’s worth paying a little bit extra in order to have that saving.

But if you’re a major house builder and you’re just going to sell the houses and then leave, the savings will accrue to the person who buys the house and lives there – not the person who built it.

What do you see of the future of sustainable homes?

The government is very keen to water down and relax standards at the minute. The Housing Standards Review is underway at the minute and it seems likely that the Code for Sustainable Homes might be axed, for example. So in broad sustainability terms, I think the immediate future looks a little bit bleak.

But for low-energy homes, I think it’s a different matter. The government is still committed to improving the standards of new homes towards the Passivhaus level and Passivhaus is still above what current regulations require.

Buyers and homeowners are also starting to get switched onto it. There was some research last year that showed people expect an energy efficient home to hold its value better and to be worth more in the long-term, so I think homeowners will start to recognise the value of having a very low-energy and energy efficient home. I think that will start to drive the market on the energy efficiency front.

In addition, as well as being a good investment for individual, high-end homeowners, I think that Passivhaus also makes a lot of sense for housing associations whose tenants are in fuel poverty to have very low fuel bills. So the future for Passivhaus could be bright indeed.

Jon Bootland is chief executive of the Passivhaus Trust.

Further reading:

Making your period home more energy efficient: a practical guide

Mythbusting on sustainable homes

Superhomes for a super future

Creating a low-carbon home of your own

The Guide to Sustainable Homes 2013


New Zealand to Switch to Fully Renewable Energy by 2035



renewable energy policy
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New Zealand’s prime minister-elect Jacinda Ardern is already taking steps towards reducing the country’s carbon footprint. She signed a coalition deal with NZ First in October, aiming to generate 100% of the country’s energy from renewable sources by 2035.

New Zealand is already one of the greenest countries in the world, sourcing over 80% of its energy for its 4.7 million people from renewable resources like hydroelectric, geothermal and wind. The majority of its electricity comes from hydro-power, which generated 60% of the country’s energy in 2016. Last winter, renewable generation peaked at 93%.

Now, Ardern is taking on the challenge of eliminating New Zealand’s remaining use of fossil fuels. One of the biggest obstacles will be filling in the gap left by hydropower sources during dry conditions. When lake levels drop, the country relies on gas and coal to provide energy. Eliminating fossil fuels will require finding an alternative source to avoid spikes in energy costs during droughts.

Business NZ’s executive director John Carnegie told Bloomberg he believes Ardern needs to balance her goals with affordability, stating, “It’s completely appropriate to have a focus on reducing carbon emissions, but there needs to be an open and transparent public conversation about the policies and how they are delivered.”

The coalition deal outlined a few steps towards achieving this, including investing more in solar, which currently only provides 0.1% of the country’s energy. Ardern’s plans also include switching the electricity grid to renewable energy, investing more funds into rail transport, and switching all government vehicles to green fuel within a decade.

Zero net emissions by 2050

Beyond powering the country’s electricity grid with 100% green energy, Ardern also wants to reach zero net emissions by 2050. This ambitious goal is very much in line with her focus on climate change throughout the course of her campaign. Environmental issues were one of her top priorities from the start, which increased her appeal with young voters and helped her become one of the youngest world leaders at only 37.

Reaching zero net emissions would require overcoming challenging issues like eliminating fossil fuels in vehicles. Ardern hasn’t outlined a plan for reaching this goal, but has suggested creating an independent commission to aid in the transition to a lower carbon economy.

She also set a goal of doubling the number of trees the country plants per year to 100 million, a goal she says is “absolutely achievable” using land that is marginal for farming animals.

Greenpeace New Zealand climate and energy campaigner Amanda Larsson believes that phasing out fossil fuels should be a priority for the new prime minister. She says that in order to reach zero net emissions, Ardern “must prioritize closing down coal, putting a moratorium on new fossil fuel plants, building more wind infrastructure, and opening the playing field for household and community solar.”

A worldwide shift to renewable energy

Addressing climate change is becoming more of a priority around the world and many governments are assessing how they can reduce their reliance on fossil fuels and switch to environmentally-friendly energy sources. Sustainable energy is becoming an increasingly profitable industry, giving companies more of an incentive to invest.

Ardern isn’t alone in her climate concerns, as other prominent world leaders like Justin Trudeau and Emmanuel Macron have made renewable energy a focus of their campaigns. She isn’t the first to set ambitious goals, either. Sweden and Norway share New Zealand’s goal of net zero emissions by 2045 and 2030, respectively.

Scotland already sources more than half of its electricity from renewable sources and aims to fully transition by 2020, while France announced plans in September to stop fossil fuel production by 2040. This would make it the first country to do so, and the first to end the sale of gasoline and diesel vehicles.

Many parts of the world still rely heavily on coal, but if these countries are successful in phasing out fossil fuels and transitioning to renewable resources, it could serve as a turning point. As other world leaders see that switching to sustainable energy is possible – and profitable – it could be the start of a worldwide shift towards environmentally-friendly energy.


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How Going Green Can Save A Company Money



going green can save company money
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What is going green?

Going green means to live life in a way that is environmentally friendly for an entire population. It is the conservation of energy, water, and air. Going green means using products and resources that will not contaminate or pollute the air. It means being educated and well informed about the surroundings, and how to best protect them. It means recycling products that may not be biodegradable. Companies, as well as people, that adhere to going green can help to ensure a safer life for humanity.

The first step in going green

There are actually no step by step instructions for going green. The only requirement needed is making the decision to become environmentally conscious. It takes a caring attitude, and a willingness to make the change. It has been found that companies have improved their profit margins by going green. They have saved money on many of the frivolous things they they thought were a necessity. Besides saving money, companies are operating more efficiently than before going green. Companies have become aware of their ecological responsibility by pursuing the knowledge needed to make decisions that would change lifestyles and help sustain the earth’s natural resources for present and future generations.

Making needed changes within the company

After making the decision to go green, there are several things that can be changed in the workplace. A good place to start would be conserving energy used by electrical appliances. First, turning off the computer will save over the long run. Just letting it sleep still uses energy overnight. Turn off all other appliances like coffee maker, or anything that plugs in. Pull the socket from the outlet to stop unnecessary energy loss. Appliances continue to use electricity although they are switched off, and not unplugged. Get in the habit of turning off the lights whenever you leave a room. Change to fluorescent light bulbs, and lighting throughout the building. Have any leaks sealed on the premises to avoid the escape of heat or air.

Reducing the common paper waste

paper waste

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Modern technologies and state of the art equipment, and tools have almost eliminated the use of paper in the office. Instead of sending out newsletters, brochures, written memos and reminders, you can now do all of these and more by technology while saving on the use of paper. Send out digital documents and emails to communicate with staff and other employees. By using this virtual bookkeeping technique, you will save a bundle on paper. When it is necessary to use paper for printing purposes or other services, choose the already recycled paper. It is smartly labeled and easy to find in any office supply store. It is called the Post Consumer Waste paper, or PCW paper. This will show that your company is dedicated to the preservation of natural resources. By using PCW paper, everyone helps to save the trees which provides and emits many important nutrients into the atmosphere.

Make money by spreading the word

Companies realize that consumers like to buy, or invest in whatever the latest trend may be. They also cater to companies that are doing great things for the quality of life of all people. People want to know that the companies that they cater to are doing their part for the environment and ecology. By going green, you can tell consumers of your experiences with helping them and communities be eco-friendly. This is a sound public relations technique to bring revenue to your brand. Boost the impact that your company makes on the environment. Go green, save and make money while essentially preserving what is normally taken for granted. The benefits of having a green company are enormous for consumers as well as the companies that engage in the process.

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