StratoSolar, received the "Most Innovative" award at this year's Harvard Business School (HBS) Northern California New Enterprise Competition. There were 15 new ventures competing. 

We are currently making progress on fabricating a small scale prototype that will be the world's first buoyant tethered object deployed in the stratosphere.

We have recently been issued two patents and three more are pending.

We are bootstrapping slow but steady progress, building credibility on the path towards demonstrating feasibility and reducing skepticism. At some point the substantial profit potential will outweigh the steadily reducing skepticism. 

Energy is about a $6T/year mostly commodity business and its all up for grabs as the pressure to eliminate fossil fuels steadily mounts. Ultimately the lowest cost renewable energy producer will win. 

By Edmund Kelly 

By Edmund Kelly

The rapid drop in PV panel prices in 2011 has led some optimists to predict continuing rapid price declines, particularly in the US. The triggering event in panel price decline was the drop in the cost of poly-silicon from over $100/kg to under $20/kg. This drop in price came as a result of investment in poly-silicon capacity which broke a cartel that had been keeping prices artificially high. This article by Matthias Grossmann describes the history in detail and focuses on the conditions necessary for renewed investment in poly-silicon production.  He concludes that poly-silicon prices higher than the current $20/kg will be necessary to get investors on board. As supply is coming into balance with demand, that increased price is already happening, so investment in poly silicon production is likely to resume.

All this means is that rapid PV panel price declines from current levels are not likely and current price levels will prevail for some time. Current overall  capital costs for large utility arrays varies from about $1.50/W to $2.00/W depending on a variety of project specific details, like local labor rates, land and regulatory costs. Interestingly,  if low cost financing is available and you have the high capacity factor of a desert, this capital cost level can produce electricity competitive with fossil fuels without subsidy, as is illustrated by this project in Dubai. However 100% project financing at 4% for 27 years is not yet the norm. For StratoSolar financing we assume a working cost of capital of 8.5% over 20 years which results in about $0.06/kWh for electricity. At 4% financing we would be under $0.03/kWh. That is so low a cost for electricity that it would be immediately disruptive in all markets and would drive very rapid growth in installed capacity. This would drive down costs which would further drive down the cost of electricity.

If we can prove the viability of high altitude, buoyant, tethered, platforms, the foundations laid by PV growth and the continuing improvement in PV technology will enable spectacular rapid growth for StratoSolar systems worldwide. 

By Edmund Kelly

This article in next big future highlights the rapid advances in large scale desalination deployment that Israel has led over the last decade. Israel, a country of 8 million people, has gone from a precarious water supply situation to a position today where 50% of its water supply is from desalination and by 2020 it will be 70%. Fortuitously for Israel this has occurred while the Middle East is in the middle of a multi year drought which would otherwise have had a serious economic impact, as has occurred elsewhere in the Middle East.

As this recent paper illustrates in detail, reverse osmosis (RO) desalination has been steadily improving and is being deployed on an increasingly large scale worldwide, not just in Israel. The Israeli company IDE is selling water from the latest plant at Sorek for 58 cents a cubic meter. That is about $690/acre-foot, or less than much of the water purchased in California, some of which costs as much as $1,200/acre-foot. As the paper illustrates there are strong  prospects for further cost reduction.

Reverse osmosis currently consumes about 3kWh of electricity to produce a cubic meter of water. At $0.06/kWh that is $0.18/m3 or about one third of the cost. Providing the energy for desalination from a cheap and sustainable, high utilization source would alleviate a major environmental concern that limits a broader acceptability of desalination, particularly in California.

Currently wind and solar alternative energy sources are expensive and worse, have a low utilization. The low utilization means desalination plants would have an equally low utilization. The combination of high cost and low utilization makes desalination powered by current intermittent alternative energy multiple times the cost from fossil fuels.

The StratoSolar solution of high utilization PV combined with gravity energy storage provides a cheap, high utilization, clean sustainable source of energy for desalination. Its lower cost over time will help further reduce the cost of clean water. The continuous cost reduction learning curve of RO desalination combined with StratoSolar electricity would reduce water costs to around $0.20/m3 ($230/acre-foot) by the early 2020s. This would make desalination the cheapest and most environmentally friendly source of water, potentially reducing some of the environmental impacts of the current exploitation of natural clean water sources.