As stated above, we want to use no more energy than can be gathered from renewable sources, from the earth area that we occupy.
There are two parts to this issue: reducing our demand for energy, and gathering the energy we demand.
Taking the first part, what can we do?
- Insulate our building, so that we do not heat up in the summer, nor cool down in the winter. It is now possible, with a range of insulating materials, and the latest high efficiency windows and doors, to make our house a total heat trap in the winter, and dramatically reduce the need for cooling in the summer.
- Use high efficiency appliances, and design our use of those appliances to also dramatically reduce their demand for power.
- Install control systems and lighting systems so that our total demand for power tumbles to 30% of the hitherto level of demand.
Taking the second part, what might our options be?
- Solar – energy landing on us from the sun
- Wind – energy from air movement
- Geothermal – energy contained in the heat of the ground below us
- Biomass – burning fuel that can be generated by our land within the time it takes us to burn it.
As our building occupies nearly 90% of our land area, we cannot get our energy from item 4.
As we are in a central urban setting, with tower blocks around, we cannot get our energy from item 2.
As we are in a part of Manhattan where the bedrock is only 0.6M below us, we are not prepared to spend over $350,000 to drill a well deep enough to tap into the heat below us, so item 3 is out.
That leaves us with Father Sun. Even if we apply the best efficiencies available, to reduce our demand for power, using currently available solar panels to capture the energy of the sun (operating at only 22% efficiency) we would need to cover the roofs of both our neighbors to gather enough energy. The reason solar panels are so inefficient is that most of the energy landing on them is converted to heat. They warm up, and release that heat out to the air above them, and it is lost to our use. So we have to find a way to capture the energy from our sun at an efficiency not currently being achieved. For the solution to this dilemma, watch this space.
Given that we are connected to the city electricity supply, we can achieve our goal by feeding back into the grid during times of plenty, enough power to offset that which we use from it during times of dearth. Technically, this is quite possible, even straight forward. All we need to do, is gather in the energy during times of plenty. Easy really!