Photo Voltaic (PV) panels are now the 3rd largest electrical generator globally in terms of using sustainable environmental principles to generate electricity. They sit behind hydro and wind, but the reason why PV is so interesting when looking at urban extensions is because they can easily be incorporated into new homes and other ancillary buildings (schools offices shops etc). By the end of 2014 177 Gigabytes were generated through PV which equates to 2% of total global electricity demand (*). The price of PV has dropped significantly in recent years and the technology that sit behind them has also improved significantly, which has made them a lot more attractive in terms of installation on new homes. However, this needs to be tempered against reductions in Feed In Tariffs, which in essence were incentives from Governments to encourage the use of them. Feed in Tariffs have proved to be very successful to date though (**).
First generation panels typically had a 14% energy efficiency rating, but this jumped to 21% for second generation, and the third generation panels will out perform this, and no doubt as technology moves on this will improve even more. So how do they work ?. A PV panel uses sunlight into solar cells within the panels to generate electricity. This is a very simple way of generating electricity from a source that is there everyday. Clearly some areas of the globe get more sunlight than others, but overall the ability to harvest sunlight is readily available, after all sunlight is free. Once installed there is no pullution or greenhouse gas emissions (***). There is currently research going in in terms of how much carbon is used to manufacture the panels and this varies widely globally, but using life cycle assessment cradle to grave methodology it is clear that overall the cradle to grave of a PV panel is highly sustainable and efficient when compared to more traditional ways of generating electricity. I believe that in the future all new homes should have an aspiration to install PV. Clearly there will be some sites or homes with constraints that do not make it feasible, but overall most new homes should easily be able to incorporate the technology. The Bicester Eco Town in the UK has an average of 33 sqm of PV on the roofs of all the new houses being built there. The advantages to the environment are clear, but the advantages to the home owner are also very clear, this will give them free electricity when the sun shines, and in the future the ability to store the electricity generated into batteries will make this even more attractive. Fuel poverty is a rising global phenomenon and PV is an important factor in stemming this. Finally, it is also very clear to property developers why this is worth investing in, as PV enhances the value of homes, and as the technology improves this enhancement will only increase (*) Tam Hunt (2015) "The Solar singularity is nigh" (**) Renewable Energy Policy Network for the 21st century (RENZI) Paris 2010 report (***) Joshua pearce (2002) "PV-a path to sustainable futures
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In order to ensure a new urban extension is delivered to zero carbon principles, and indeed bring the other gains mentioned in this blog, it is crucial for a monitoring period to be introduced once the urban extension is occupied, so there is a clear data log to ensure the benefits are being achieved.
In order to ensure this is incorporated, it needs to be a planning requirement for the development, either as a condition or as part of the legal framework put in place to grant the consent. This ties in any property developer and means they are committed to this for a defined time period post occupancy. In order to make this condition have teeth, there are examples where the legal agreement accompanying the planning permission has financial penalties built into it if the monitoring is not carried out, and indeed also financial penalties if the results to do not deliver the agreed aspirations as set out in the conditions. For example a condition may be that car use has to be 50% of the rate of car use when comparing the urban extension to the wider City car use statistics. When the developer is clearing conditions it would be a requirement for them to put in a robust transport strategy outlining how this can be achieved, and this could incorporate things like real time information at bus stops within the development, no bus stop being more than x meters from any of the homes, a car club on the site for shared use, strategically designed footpath and cycle routes throughout the urban extension to encourage cycling and walking to key destinations and so on. In the Bicester Eco town in the UK all trips for the wider town were analysed and it was shown that a significant reduction in overall car use could be achieved if 2 key things were delivered in terms of behavioural change, and these were school runs and what were described as the small runs to the local shop for milk and other small items. The overall design of the urban development goes into great detail in terms of just how easy it is to access schools to be built within the extension and shops within the extension by bicycle or walking. A further important sustainable avenue that was accepted for Bicester was allowing electric cars to not be counted within overall car trips, as this clearly encourages the developer to offer incentives to all occupiers to invest in electric cars. At Bicester the lead promoter of the site has placed electric charging facilities in all the garages for the homes, and also communal electric charging facilities throughout communal parking areas across the site, and the developer also has formed a partnership arrangement with an local electric car provider to offer incentives to new occupants of the development not open to others. The overall monitoring would need to cover travel patterns, water use, electric use and overall energy efficiency within the homes. Water and electric use can be easily monitored by introducing technology within the homes (smart meters or a specific monitoring device that feeds a central server for all the homes), and this technology is relatively straightforward to incorporate into the design. At Bicester all homes were provided with a "shimmy" device which is about the size of an Ipad and can be attached somewhere in the home to capture this information. The great thing about a Shimmy device is is can also have other uses, such as providing real time bus information to residents, or letting them know when the car club vehicles are free for booking. This monitoring over time is a highly useful and valuable tool, not just for the home owner and the developer, but also for the planning authority and the Government. The Government has committed to reducing emissions along with other other international partners, and it is crucial for any Government to be able to monitor this in terms of new developments so it can robustly show further down the line that the benefits are tangible and deliverable when looking to further legislate in terms of how sustainable the homes of the future should be As a follow up to the existing theme of creating sustainable zero carbon urban extensions, I will now look at water. Water is an important resource globally and the development sector should as a principle look at ways to use this precious resource as efficiently as possible. In order to look at the bigger picture, so not just the individual homes being built to zero carbon principles within the urban extension, it is important to incorporate as many other sustainable principles as possible across the development. The home is a good starting point though. The aspiration is for all new homes to use water efficiently, and an easy win is designing and installing the taps and showers to low volume principles where their use is hardly noticable from the current accepted norm. Another sustainable principle that is easy to deliver is rain water harvesting. This can be done with an individual system per property or done on a communal basis and shared by a number of properties. They are relatively easy and cheap to install and allow the use of water for flushing toilets within a house which would normally be potable water from the water main. Water butts within garden areas that capture rain water run-off from gutters is also an excellent way to use water for outside purposes such as watering the garden area. In terms of the wider urban extension, the role of Sustainable Urban Drainages Systems (SUDS) is crucial. These systems are now a legislative requirement for new developments in many countries. SUDS are effectively designed to slow and hold water. The benefits are huge and include :- Slows and holds water which allows natural processes to break down pollutants Recharges Ground water to help prevent drought Prevents flooding in urban areas Creates natural habitats for wildlife Permeable paving on road or footpath areas stops run off and feeds into any SUDS system Most SUDS are a combination of swales (shallow drainage channels) and bigger ponds which all interconnect. A final observation on SUDS in terms of sustainability for a house is the use of green roofs. These roof have huge benefits as they reduce run off, add insulation, cool property during the summer, increase sound insulation and also provide a habitat for wildlife. All of the above has been incorporated into the first phase of the Bicester Eco Town in the UK (*) (**) (*) nwbicester.co.uk www.ecobicester.org.uk In the current climate, where there is a high demand for new homes within an urban area, the land at the fringes (often termed greenfield) becomes zoned from a planning perspective to help facilitate growth, and this is usually in tandem with other policies which encourage brownfield sites (for example sites already within a city that may be derelict industrial space) to deliver new residential development too.
This is a very common approach globally and tends to lead to higher density development in existing central brownfield areas and lesser density (per acre or hectare or sqm) on the fringes where the space constraints are less. In order to deliver new developments to adhere to zero carbon principles inevitably means the construction of both the homes and the supporting infrastructure will be in excess of a traditional new housing urban extension, so to enable it to occur there needs to be certain criteria in place to help deliver it that sets it aside from the traditional route. The increased costs associated with this kind of development inevitably hits the land value in the overall development financial stack, but what is hoped will be achieved in the future is for this to adjust if more and more developments such as this come forward, or even become the norm, and the supply chain adapts to focusing on delivering greener materials in bulk, and sub contractors adapt to installing these newer products competitively. A key determinant is whether the demand for new homes is so strong that having legislation to enable a suppressed land price will still encourage landowners to sell. In the UK the Government researched in depth suitable sites for urban extensions that could fit this criteria and Bicester was chosen as one of them. The key attractions for picking Bicester against other areas was the existence of very good train and road links already in place, the fact that there was 1,000 acres of farmland that could fit into a masterplan to deliver circa 6,000 new homes and ancillary uses, and it's overall strategic location within the south east of England (which is an area where the demand for new homes is huge). Having 1,000 acres of farmland available meant that negotiation with the landowners could be on a very large scale, so even though the price per acre (or hectare or sqm) may be less than competing traditional developments, the overall quantum to the farmers still made it highly attractive. Once the land is identified as being potentially suitable for such a development, it is then important to establish a robust legislative framework that only allows residential development to occur there if it is to zero carbon standards. In the UK this was achieved by having a Supplementary Planning Document (*) put together at a national level, that could slot into the strategic Local Plan put together by the planners at a Local Level. This led to the promoters of the site at Bicester to formally submit a masterplan for the site, and once approved, the masterplan could be a supplement to the Local Plan for within the local Plan period (which runs until 2031). Without having these legislative and planning tools in place, it would not be possible to ensure only a zero carbon development could be delivered. Why is this important ?. Climate change and the fact that finite unrenewable resources are being reduced year on year means that we cannot simply continue as before forever (**). There has to be change, and the UK as part of the EU and as part of wider international groups, has committed to meeting certain targets on climate change going forward. It is therefore of great importance that it can be shown that large urban extensions can be delivered to these principles to show the wider house building industry it is possible, and is indeed possible to achieve with the normal profit levels associated with risky speculative residential development (which is normally expected to be around 20% if funding is to be attracted to the development). (*) www.gov.uk/government/publications/eco-towns-planning-policy-statement-1-supplement (**) Kyoto Protocol Continuing the theme of a Zero Carbon residential urban extension, this blog will explore how such a development can be designed in masterplan terms to aspire to a healthy and greener lifestyle to complement the green homes. The use of the green space within the masterplan is key to this. A strong masterplan needs to be functional and encourage the new community to embrace the outdoors. Having strategically positioned footpaths and cycle paths through the green space that efficiently connect the residential areas of the development to the non residential functions, such as shops or schools or employment areas, can make it attractive and easy for shoppers and children and workers respectively to walk or cycle to these services. This is evidenced with the Bicester Eco Town masterplan carried out by Farrells architects in the UK (*), where the road network within the proposed residential areas was deliberately designed to be more inconvenient in terms of traveling by car to the other uses across the masterplan. Also, having formal or informal areas for sport within the development which negates to need to travel by car to other facilities within the area is very important. This, along with cutting our car trips to the schools and shops and employment areas mentioned above, reduce the use of the car and therefore reduces the fuel needed and the pollutants associated with driving. Encouraging walking and cycling and sport also has a big indirect benefit to people's overall health, and therefore a lesser economic burden on local health services. At Bicester in the UK lots of allotment space has been designed into the masterplan, as this clearly encourages local food growth either for individual occupiers or if the individual occupiers decide to form a local Management Organisation where they can produce food collectively and either consume themselves or sell at local markets. To conclude, well designed landscape space greatly complements the ethos of building zero carbon homes and takes the thinking further to engender other facets within the overall concept for a new community (*) www.farrells.com/projects/bicester-eco-town This second blog entry looks at what is needed to build zero carbon homes as part of an urban extension, and the potential barriers for doing so. In order to design a home that is zero carbon the carbon dioxide emissions from the home have to equate to zero over a defined period, so for example a calendar year. The way this can be achieved is by comparing the carbon needed through a traditional home both in terms of construction and use of the home when built, and offset this by using technology and different building techniques to demonstrate this. Within an urban extension setting this means it can be looked at in a large scale way. For example rather than having individual gas boilers to each house a combined heat and power system (CHP) can be used that only has one connection to a gas grid, and this runs engines within the CHP that provides heat and hot water to all the homes through a district heating system (essentially pipes to all the dwellings). This has a much lower use of gas than having individual boilers to, say, 400 new homes, and the added benefit of a CHP is the generators produce electricity which can be exported back to an electrical grid, which in effect adds to the pot of sustainable energy produced on site and offsets the traditional use of electricity being produced through carbon, as in effect it "gives back". All the homes can have extremely high insulation levels and air tightness, triple glazing, and significant Photo voltaic (PV) panels on the roof. The high insulation and air tightness significantly reduces the heat needed for the home, and the PV panels if singnificant enough can also produce electricity to be exported to the grid along the same lines of the CHP, or alternatively as technology moves forward this electricity can be stored in batteries and used for the house in night hours. It has been proved that this can be delivered and the earlier example of the Bicester Eco Town (*) (**) in the first blog is an example. In terms of barriers, it is currently circa 202 per sqm to build a home to zero carbon over and above a traditional form of construction (Bicester Eco Town 2016) and this does not allow for the additional cost of having a CHP and district heating system (but which is partially offset of not needed all the individual gas boilers and the district gas network as well). Clearly this will put off developers if they cannot see a premium for the homes as it will give them a disadvantage when bidding to buy the land. However, as stated in the previous blog, if the market conditions are correct for a particular location and there is the will of the local planning authority or legislation to allow it to happen, this can ensure the delivery of zero carbon homes. In the UK the purpose of the pilots is to prove to the market it can be delivered on a large scale for a normal profit that property development commands, hence specific legislations to enable it to happen (*) nwbicester.co.uk (**) www.ecobicester.org.uk The world in which we live in has seen huge population growth over the last few decades, especially within urban environments. The issues surrounding this are immense and complex, but it is clear that the earth has finite natural resources, and it is clear that human activity increasingly favours politically and economic activities over issues surrounding long term sustainability despite a huge layer of research highlighting the dangers, and if future generations can enjoy the earth as previous generations have it is clear that ideas and concepts surrounding sustainability need to come increasingly to the forefront. This blog will look at individual layers of sustainability as the blog develops and the first blog post relates to Zero Carbon.
It will be within a context of both national (*) and global (**) legislation. The concept of zero carbon when developing something is to ensure the net carbon dioxide emissions from all energy use from what is built is zero over a measurable period of time. In the house building industry this is only being pioneered in relatively small chunks worldwide, and this is primarily to do with the greater cost to develop a zero carbon home, or even an urban extension of zero carbon homes, when compared with more traditional forms of construction. Inter alia, this means if a site for development for an urban extension achieves a planning permission to build, for example, 400 homes, and is taken to the market, all property developers interested in acquiring the site will have to bid competitively to acquire the site, and if there is no specific legislation attached to the planning permission regarding having to achieve zero carbon homes, nobody will bid on that basis, as clearly they will not be successful. What is interesting is where globally Government's are producing legislation to pilot certain urban extensions in planning terms to insist this happens. A well designed zero carbon home has proved popular to the market when built and there is evidence to show that, although the home may not demand a premium on more traditional forms of construction, it certainly sells quicker than other similar sites within the same geographical location. This is primarily due to purchasers knowing that the running cost of the home will be cheaper than a traditional home, and also because there is a growing number of people who wholly buy into the concept of sustainability and what it means for future generations. Examples of this are the "One Brighton" project carried out by Crest Nicholson in the UK where they constructed 2 blocks of flats adjacent to each other, where one had higher eco credentials than the other, and although there was no premium attached to the block with higher credentials, it sold a lot quicker than the other block. Another good example which takes the concept further as the planning permission stipulated zero carbon, is the urban extension at Bicester in the UK which is a designated Eco Town under legislation pertaining to PPS (Planning Policy Statements) and more specifically PPS1 which is an addition to legislative PPS and specifically deals with sustainability. This meant the land within the urban extension is designated as zero carbon and can only be acquired and built out if it adheres to a specific set of principles. The first phase of this urban extension completed in 2016 and the new homes sold for a marginal premium above competing developments and also sold quicker. The important point though, is it needed specific legislation in planning terms to stop the site simply being developed in a more traditional way. This has the effect of significantly reducing the land value, so it is crucial that any planning permission of this nature has to be granted only in areas where the land is still likely to be sold when suppressed. (*) Victoria State Government Climate Change Act 2017 kyoto Protocol - unfccc.int/kyoto_protocol/items/2830.php |
AuthorGerald Walker. BA Hons Economics and Studying for a Masters at UNSW in Property and Development Archives
June 2017
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