This project is my own little effort to tackle two of the major problems facing the human race – Climate Change (from CO2 emissions) and Energy Famine (due to the lack of further fossil fuel reserves, and the problems caused by burning this energy source).  Whilst many deny that either of these are a problem, the majority of educated people recognise that these are risks that require action, now and not when it actually happens!
     In every other part of our life we take insurance – we insure our car, our house, our travel, our belongings, our health – we consider the risks, and often the event doesn’t occur, but we were grateful that we didnt crash the car or break the leg on a ski holiday. In the same way, we need action now, as an insurance against a future risk.
     One small house achieving Carbon Zero is not going to prevent climate change, but this project is more about education and enlightenment. If enough of my students, and the readers with an interest in renewable technology are inspired by this, then the idea moves ever outwards to a wider audience, who in larger numbers can make a difference.

My other two major risks are Increasing Population (with increasing energy consumption due to rising living standards) and Food-Water Stress (with high food miles to maintain the quality and variety we expect, while in other parts of the world, there are major shortages). There is little I can do about these two as my children are both grown up (and not yet making grandchildren). Food-water wise, we grow what we can, we go for local food if possible, nothing is wasted (the cat, birds or compost heap get what we don’t), we capture rainwater for garden use, and we already use year-2016 levels of water.
   These threats are all interlinked – for example, increasing populations demand higher living standards, more mobility, food requires energy to cook and transport, burning of energy adds to CO2 emissions etc.

Food and Energy
Humans cannot live without burning energy, we have biologically adapted over the millenia to burn energy in order to eat. No matter how well we insulate our buildings, and even if we gave up electric light, computers and TV, we still have to burn energy to eat!
The original hunter gatherers of the Olduvai Gorge in Africa may have been able to browse seeds, leaves, fruit and carrion every day and drink at waterholes, but the moment we migrated north, we had to learn how to store food during the winter, make clothes, and we discovered that meat cooked on a fire was vastly safer to eat, and more calorific than raw meat, and that water boiled was safer to drink. Where every other species on the planet can eat raw meat, raw vegetable material and pond water (depending on their position in the environment and food chain), we would rapidly suffer food poisoning, parasite infestation, or at best severe indigestion if we ate anything raw other than fruit and a small number of vegetables. The enzymes in our stomach simply cannot cope with grass, twigs and raw meat; they have changed, in the way that our skins have shed hair when we began to make clothes. Some animals actually thrive on putrefying meat (vultures, crocodiles, insects) whereas we have an instinct to retch and vomit if food is unclean. Over years, our gut has shrunk to 60% of the size of an animal of our equivalent size due to our rich diet of cooked food, and our jaw bones and muscles and teeth have evolved so that we can no longer bite through leather, bone or feathers. There is no going back, unless you wait thousands of lifetimes.

The average British peasant prior to the Industrial Revolution had a staple diet of the four B’s, Bread, Beer, Bacon and Beef.
• Bread could be baked because humans have learnt how to store and transport grain for millennia.
• Beer was safer to drink than water because it comes from boiling grain, and the alcohol is a preservative.
• Bacon symbolises all the forms of meat that are salted, dried or smoked, to preserve them.
• Beef was necessary as it is self refrigerating food that walks about on 4 legs, and lives on storable materials – grain, hay etc.

  Of course we had more than just the 4 Bs, we had Milk and Mutton and a few others – but Fruit was never seen, except during the very short harvest season. Tea, Rice, Tomatoes and Potatoes are very recent newcomers to our diet. Other cultures, such as the Mediterranean learnt to make similar methods of storing produce from Olives and Grapes. Urn making and shipping of urns, and the building of those ships to move around the Mediterranean basin were all a major industry, attested by the uncountable number of sunken ships and scattered urns on the sea bed.
   I haven’t got space here to discuss Water at length – but this is fundamental to our existence, and the way that it is delivered now is highly energy consuming, and yet more than half of it is flushed down the toilet. Shortage or pollution of water (and the disease or starvation that follows) has often been the cause of the ending of previous civilisations. Today, much of our water could be captured off our roofs to supply all our non-potable requirements. I am shocked that some of the major new cultures such as Dubai are dependent on desalinated water, but developers persist in building skyscrapers with swimming pools and a bath for each bedroom.

Climate Change and Energy

• Climate Change: I believe that our climate is changing due to human-activity caused emissions of greenhouse gases. CO2 and rising temperatures may not be seen as a problem, but a greater danger would be substantially rising sea levels from the melting icecaps and the albedo effect in frozen land regions causing release of methane. This could bring a change vastly greater than the end of the Ice Age, because the world population is billions greater than it was as we have rigidly established cities and boundaries. I have no time for outright deniers, because the fact that solar heat is trapped by an atmosphere higher in greenhouse gases is a fact of physics, like gravity or light. For those who assume that climate change is the same as ‘global warming’ we should patiently point out that ‘weather’ is different from ‘climate’ – if climate change can affect ice levels and alter ocean currents, some places, like the UK, will get colder not warmer.

• Energy : I also believe that the reserves of fossil based energy are expiring and that energy consumption is so essential to our way of life that to be without it will cause wars, invasions and breakdown of civil existence. Human kind is ignoring the major source of energy that is available, the Sun, and we must find better ways to use it.

Discuss: Climate Change
In the past, we adapted to climate change and rising sea-level by migration, sometimes invasion of the land of weaker species (what did happen to Homo Erectus? they got killed!). We know that ancient tribal people made use of the land bridges that still existed at the end of the ice age, eg from Siberia to Alaska, Europe to Africa, Britain to France, etc. and the abundance of animals to kill and trees to cut down.
  This is no longer possible with our national boundaries, governmental organisations. Even a small amount of economic or climatic migration causes a national panic, and the rise of new political groupings such as the US Tea Party, or the BNP. Similarly,  if the average temperature rose by 2 or 4 degrees either way, you might say we can just turn up the heating or the air conditioning. But this requires immense energy consumption, and more CO2 emission, and is not a solution for millions in the already-hot countries.
   I don’t have a problem with climate change deniers – they are entitled to their opinion (but I don’t want to be friends with people like this). Many of them admit it’s happening, but deny that humans are the cause. Some of them admit it’s happening, admit it’s down to human caused CO2, but say it’s too late or too expensive to do anything about. They are often the kind of people who are also most against immigration or energy conservation, or energy generation. They certainly don’t see the need for them to change their own behaviour behaviour.
  Even if you don’t believe in Climate Change, we should all be in the business of Climate Protection – mitigating possible change, and reducing pollution.

Discuss: Energy
What most of the Climate Change deniers cannot deny is that Energy is becoming more and more difficult to find, and more expensive. And if they are reasonable, they would admit that our society uses far more energy than is necessary for life – shops brightly lit all night, floodlighting, dependence on private cars, air transported flowers and food etc. Our economies are predicated on annual growth, and growth usually means higher living standards and higher energy consumption. Politicians are usually elected by promising growth, not cuts. Growth always seems to result in higher energy consumption. Despite Kyoto, Copenhagen, Durban, and all the other attempts to curb climate change, the CO2 emissions are now higher than ever before. The continuing use of energy on this scale is unsustainable, especially the high consumption in the rich countries, who are dependent on buying the energy from (previously) poor countries, and the number of countries who neither produce nor consume, and sink deeper into ‘energy-poverty’. The degree of anger that results from a shortage of energy causes huge conflict. The invasion of Iraq is just the start of a number of energy conflicts that we will see increasingly.
   The Olduvai theory (Link) postulates that there could be a complete breakdown of society after 2030 once large populations cannot have energy to get through winter, cook, travel to work, get to shops or education, find anything in the shops, have electricity for 24 hrs, or take holidays, etc. Looting shops and neighbours would become an essential survival strategy as occurred in New Orleans in 2005. People with the food and the guns (eg like the survivalists in present day Montana, Nebraska etc) would hunker down and defend what they have against ‘the government’ or weaker members of society.
   As energy becomes harder to find, pricing mechanisms slowly catch up, and force people to use less of it – but the price is still too low to move us all over to a Green energy economy – at 3.5 pence per kilowatt hour for Gas, who needs to economise? Electricity prices did not change from 1986 to 2001 because North Sea oil and gas made price rises unnecessary. They have trebled since 2001.

This discussion could go on a long time, I might write more later. Meanwhile, I will cut short and shift back to the Peveril Solar house project

Where does the house project fit in?
I believe that we should not wait for ‘the government’ to do something about it – we individuals all have to do something about it, right down to the buildings we use and the food and transport choices we make. We can find ways to reduce the CO2 emitted by our existence on this planet.
    As a teaching architect, it is clearly my duty to discuss these issues with my students – in fact we have a number of Masters courses at my University which address this issue, and my own design modules specifically require Sustainability as a driving force.
    When I had the opportunity to move to a new house in 2006-7, it was a wonderful chance to do something positive to save energy – our previous old detached victorian villa has burnt huge quantities of gas for heating and cooking. Existing houses are difficult to adapt, new-build houses are easy. So we decided to use a Heat pump, and because of the shape and position of the site, ground source with a vertical borehole was the only option. I had two ancient aunties leaving me money, in 2006 and 2009, whose legacies funded some of this work. The construction of the house meant that it could not be as good as a Passivhaus… but with a bit of work, it can be an Active House.

So, in a nutshell, the recent project is two fold:
• Power UP! – to Generate energy [hence the Photovoltaic], and
• Power DOWN! – to Conserve energy [by making the heatpump more efficient, hence the ‘Charging the Earth’].

Photovoltaic is well established, and was a quick day-and-a-half to install. Install, and Enjoy!

The reason that the Blog is mostly about the Solar Earth Charging is that this is innovative, risky, inventive, developing, incomplete, may never happen, time consuming etc. It is a learning experience that has been for me, life changing, and it would be great if it evolves a technology that will be used to supplement ground source heat pumps and MVHR systems in future.
Why are these called Surya Sunboxes? See the article explaining this.
So….. I am claiming that the Peveril Solar house is Carbon Zero… Hmmmm…. What does this mean? (There are plenty of definitions if you google for them). In a nutshell it means your building is operating in a way that it achieves net zero carbon dioxide emission – what it burns is balanced by what it saves or generates.

We do burn electricity, but we generate also, so that others may use what we generate and thus they avoid burning. In the overall equation, measured annually, we achieve the carbon balance, and do better than that.

This is different from a house that is off grid – in our case, we use the electricity Grid as a battery to take power from in Winter and to put power into, in Summer.

We are not carbon zero in our total existence, if you include power tools, lighting, cooking, TV etc. That is impossible at the moment with the government limiting PV installations to 4kW and us not having a south facing roof. Most definitions of carbon zero in the building industry apply to ‘regulated emissions’, i.e. those which are metered and part of the primary operating of the building – heating and cooling. Even the renowned disciplinarian Professor Wolfgang Feist (of Passivhaus fame) allows people to have a life – ie. cook, have showers, shave and watch TV.

Actually….. we are fully carbon zero for that ‘lifestyle gap’ in that we buy electricity from Good Energy, a 100% renewable energy supplier. That is good, but it is an economic ‘workaround’ which would make a solid-walled, single-glazed house with electric heaters carbon zero, which is not the ‘true pathway’ to carbon zero.

How does this equation work for the house? I re-compute the annual figures every Sunday.• During 2011-12, the GSHP total consumption for the year has gone below 3,000 kWh, for a total of space heating and domestic hot water and the floor circulating pump.• Deducting the underfloor circulating pump (which uses 300 kWh during the winter months, the GSHP’s consumption annually is less than 2,700 kWh. Of this, the Heating component is about 2,100 kWh and the balance is 600 kWh for DHW.• The PV-Roof achieves an average generation of more than 3,200 kWh/year.Therefore, the Heating and DHW are in balance with the PV!
• Including all lifestyle consumption (lighting, power, cooking), our annual meter averages 5,000 kWh. This used to be 8,500 kWh/year before the PV and Sunbox project.
• If we did not have a PV roof, the total house consumption, including GSHP and all other power would be about 1700 kWh more, i.e. 6,900 kWh.
Purists would demand that in addition, we should make enough power, or reduce heat loss enough for the PV roof to cover Cooking, Lighting and Appliances too. Yes. I agree with this eventual target. But it is hard to reach, believe me! Even the Passivhaus standard does not expect this. The UK tariff system does not favour householders installing more than a 4 kW array, so it is not possible to raise our power generation beyond 3,300 kWh, short of rotating the house to face south, and having a larger roof! I would willingly instal enough PV to generate 5,200 kWh a year if the roof was larger.

They would also claim that we should consider our water consumption, as energy is required to capture, store and deliver it. In the Peveril Solar house we are already living below the 2016 target of 80 litres/head/day, and catch rainwater for all garden use.

Advanced Purists would also point out that the very fact of being in a house at all is making a carbon impact because of the embodied energy in the brick making, concrete, glass, steel etc. Well, as society does not accept people living in ditches, squatting or living in trees, we are all on a level footing on that – logically, we should be prepared to live in smaller houses, with a higher content of recycled and recyclable materials. Moving to a very old house whose embodied energy was paid off 100 years ago is irrelevant if the insulation is so non existent that the present day operating energy costs are enormous.

If you were to pursue this to its conclusion, you would not be able to buy food from shops or supermarkets (food miles), eat meat, eat salad, eat fruit, have a car, live in a house, take holidays, travel to work, wear clothes or have children. All of these require the consumption of energy. So let’s agree to define Carbon Zero for buildings as applying to regulated balance of emissions and consumption.  

There is a link between what I am doing with the wider issue of Sustainable Technologies, with the prospect of the year-2016 looming up closer.

In a nutshell: If the UK building industry is to move to carbon zero (or ‘carbon neutral’) by 2016, I think this technology of solar earth charging (UTES=Underground Thermal Energy Storage) will be essential. Carbon Zero cannot be done solely by improving Insulation – this would only be Code 4. We also have to think about Systems, primarily for heating (in the UK environment), and the UTES technology can be used for cooling in Hot environments.

If our deeper purpose is to avoid emission of carbon into the atmosphere, considering three primary methods that avoid burning COAL/GAS/OIL. Renewable electricity is the alternative to burning, and the Sunboxes could be a real benefit to heat pumps, one of the key technologies that is going to work in future.

Three stages of energy

1. Sunspace – and high thermal mass, with heat reclaim (MVHR) powered by PV/wind – Hockerton style. These houses are ultra-wide frontage, very expensive in construction and cannot be applied en masse admirable as they are. They are not being copied in the volume market, brilliant as it is. It is low density and very demanding as to site positioning and lifestyle. All houses have to face south with large conservatories and massive thermal construction underneath and earth-sheltered roofs to the north. Very few developers will build houses with a managed sunspace facing south, and earth roofs. In the wider housing industry, the conservatory business is doing well, but commercially supplied conservatories seem to be decorative, not actively used for heating the house. (I designed and built a house in 1982 that had a heat reclaim system drawing heat from a conservatory, and using a central thermal store.) I don’t believe that the SAP calculation knows how to include the effect of a managed sunspace and huge thermal capacity any more than it does a sunbox augmented heat pump.

2. Biomass – wood burning – it might only be theoretically ‘carbon zero’, because the wood was grown in your own lifetime. But it still involves burning and emitting smoke particles, and cannot be employed en masse for population, smoke and forestry reasons. It is a great back up to a primary heating system, but not for dense urban areas. There is massive work required in cutting up logs and pallets, and cleaning out the stoves etc. It requires very reliable ventilation to provide combustion air, unless you have special stoves with ducted air intake, etc. If the wood-burning stove has a back boiler, this is a good way to remove heat to a tank for it to contribute to water or space heating. You can have wood delivered as special woodchips, which works well in Austria/ Switzerland. But if your woodchips are transported a long distance, consider the ‘chip-miles’.

3. Heatpumps – as used in over 90% of new houses in Sweden (ground source) – surely, this is going to be the answer, because being powered by electricity, their fuel source can be generated by hydroelectric, nuclear, PV, wind etc. , and efficient heat-pumps can manage heating and hot water. There are new Feed in Tariffs starting in 2011 to incentivise more use of Heatpumps. The heatpump uses some electricity to get vastly more heat from a warming medium – the air, water, the ground under or near the house….. Or in my case uniquely, a hybrid of Ground, Air and Solar.

[4. I have not included CHP (combined heat power) in this discussion because it burns fossil fuel, and it produces more heat that we really need in a well insulated building. But see another article on this, because there can be benefits.]
[5. I have not included CarbonOffsetting, as that is just a procurement decision, and not about the design of buildings or systems. On this offsetting basis we were already Carbon Neutral because we buy energy from Good Energy’s wind farms. We could be irresponsible, and live in a badly insulated brick house with electric fan coil heaters and falsely claim to be ‘Carbon Neutral’. See above.]
[6. I did not include Solar Thermal in the list because this mainly applies to Hot water, not to house heating. But my friend Karina Wells has a water tank that is heated by solar thermal and contributes energy-saving to the gas central heating system.]

So, let’s discuss Heatpumps :-
Electricity is too expensive to use One-to-One, so a One-to-Three or One-to-Four conversion ratio is a way to stretch it further – by burning one unit of electricity in a pump and fridge unit, you hope to get 3 more from a heat source like Air, Water or Ground, or a mixture of those.

• Air source is good, expecially if the existing plumbing makes it easier for them to be a ‘boiler replacement’ in existing buildings. They are working in an almost infinite flowing source. But in cold climate winters, air source is not so good – even in our mild climate they may use the immersion heater function too often. They are somewhat noisy for houses close together. They are used more for Retrofit, and Ground source more for Newbuild. But Ground source can be added to existing houses if the radiators can be swapped for more efficient units.
• Water source is very good for those with access to river, lake or plentiful groundwater – not a solution for en masse housing, and so rare that there is not even a Wikipedia page about water source HPs. Running water is better – if you drew heat from a static water source such as large rainwater storage tanks, there is too high a risk of freezing. If the river runs fast, there is a danger of the river bed shifting and your pipes being exposed or swept away.
• Ground source works well in cold or hot climates, if you can face the initial cost of laying the pipes or boreholes. To my experience, ground source has the problem of declining ground temperatures and surprisingly high electric consumption. GSHP has a high cost for en masse use unless made more efficient. In a dense urban area, there isn’t enough land for horizontal ground source, so deep boreholes become necessary, despite the cost.
Is there a way to make these more efficient? I believe that there is!

   Ideally, you would ALSO have Solar thermal panels for Hot water but it is difficult to adapt this for heating! Solar Thermal needs a large tank and is expensive. Thermal panels can significantly augment the process of Water heating even for a ground source heatpump – but will they help with House Heating? Well they will if you use a ground source heatpump as your ‘thermal manager’.

So I ask: 
Why not use solar panels to heat the warming medium used by the GSHP? What if we can use Ground source, but get the Solar heat down immediately into the ground? Do it This year, NOW! not wait until solar heat finds its way down there Ten years later? The Sunboxes show a way to do this.

Solar heat falls on the ground to replenish the deep soil temperature, but becomes less effective in urban areas because the ground is closely covered with highly insulated houses, or green landscaping that shades the ground… not enough tarmac or open space. By the way, next to our house in Nottingham, there is plenty of tarmac and open field, so solar heat does get down, but would not be effective if everybody was doing it. Even if it does work, it takes decades to get down 50-100 metres.

If clusters of houses are all drawing heat out and not putting any down, that is unsupportable in the long term. If the developer adopts Sunboxes, the whole cluster of houses are also pumping solar heat day-by-day deep into the ground, winter and summer, so you don’t need acres of tarmac around to pick up the solar heat. The denser the houses (and well insulated in their slabs) the more likely that sunbox-captured solar heat is to stay down below where it is wanted.

How about ‘Energy Foundations‘, where the HP draws heat from immediately under the building? Can this be done? Well This is an idea that Chris Wood has been working on. My team are designing a colony of houses doing just this! Sunboxes pumping heat into the foundations, and Heat Pump getting it out again. I also have my postgraduate students working on skyscrapers that can work with solar charging, storing summer heat in large stores of PCM.

Urban opportunities
I am mooting the idea that urban areas could have a large number of sunboxes conveniently posted on walls or roofs, often integrating well with buildings, which are conducting solar heat directly underground.

Urban Solar development

   In dense urban areas, the ground is shaded by the trees and well insulated buildings, the tarmac loses as much as it gains and is largely covered by parked cars, and shaded by trees in summer. The visible areas of tarmac are not enough to store solar heat ‘accidentally’ – so something more deliberate needs to be done. Sunboxes are cheap as a technology, and can be unobtrusive (looking rather like a window), can fit between windows, as part of a facade, in the valley between roofs, between dormers, or even as part of a balcony surround.

West london

1.  The overhead photo (thanks to Googlemaps) shows an area of West London, typical of city residential density. This photo makes my point about the trees and the parked cars. But there are plenty of roof spaces where sunboxes would not even be visible to ground level. The problem here would be laying in ground pipes. But I remember when Cable TV was being laid in Nottingham 20yrs ago, every street was dug up for cabling! Didn’t take long.  There is a new generation of small diggers, small enough to fit through a house door (for excavating ground floor slabs), so it is possible to plant slinky Ground loops in domestic back gardens.

City of London

2. The middle photo show the square mile of London, with key buildings many of which now use CHP on a vast scale, some have boreholes for cooling and for heating, they all have plant rooms. They all have a high capital value but high running costs, making it a worthwhile investment to instal energy saving systems. Sunboxes work better on wall than on roof, and tall buildings have plenty of wall surface. Sunboxes can be part of a double facade construction. Just as the Heron Tower (just north of the picture) has a whole south wall of Photovoltaic, but also has a high level of transparency, Sunboxes are just a double skin with thermal collectors which do not need to occupy the whole space – so you can see round them and through them, and they can include PV in patches.

London Barbican

3. The Barbican development is one of the most successful London districts, being of mixed use (residential, cultural), and of mixed height – built in late 60s early 70s. Developments on a large scale like this can justify investment in district heating, boreholes, energy centre (for CHP), and for large scale heatpumps delivering to many residences. A new development can incorporate sunboxes so easily that the the viewer would just see them as part of the facade, if they realised what they were at all.

Is it so unreal that heatpumps could be in the majority of households in the long term future? Well you only have to look at the food retail industry to see how supermarkets and frozen food have made it essential to preserve food in refrigerators. There not been a private market or council house built in the last 50 yrs that included cold cellars or traditional larders.  Fridges are so commonplace that there are now ‘fridge mountains’ of thrown-away fridges when people upgrade to better models.  If very expensive refrigeration technology can be built in sufficient numbers, it becomes very cheap – and fridges are the most reliable appliances in the home. Heatpumps are simply large scale fridges, with pipes attached – they could become a lot cheaper!