This week, I had the opportunity to speak to technology vendors at the Intersolar Conference in San Francisco that are targeting the payback from solar power from different angles. Xerocoat and Adept spoke of plans that will help reduce the cost of solar energy, while Schuco presented products that seek to ensure that buildings not only conserve energy, but also generate it.

Xerocoat manufactures a coating for solar PV panels that increases efficiency through greater absorption of solar energy. Their coating is about 100 nanometers thick. According to the company, early test results indicate it does not easily degrade over time. Xerocoat says the coating increases power output by 3 percent, meaning it has great potential for application to large-scale solar panel systems. For example, a 100 megawatt plant would see profit increase from $4.5 million to $8.5 million from the added energy production. The anti-reflective coating is marketed to module makers who do not have to change the manufacturing process. If PV panels can produce more energy per module, the relative cost goes down.

If Adept Technology has its way, robots would take the place of people in assembling solar panels. Automating the process would reduce the cost of solar as robots cost less than laborers, according to the company. Today's robots operate at 25-40% of 1990's costs and provide additional cost savings by allowing automation in inspection and handling.

Solar robotics make up only 15% of Adept's business today, but the company has plans for greatly expanding that part of their business. For example, the company says processes ideal for future automation include laser scribing, assembly, tabbing and stringing, and machine loading and unloading.

Schuco presented a building envelope plan that not only traps and conserves energy, but also generates it. Schuco's product line is focused on harnessing the energy saving potential in heating and cooling buildings. The company has created a Technology Center, which they've outfitted with much of their own products in an effort to reach 50% reduced CO2 emissions. Upon final inspection, they exceeded their goal, attaining 54% reduction.

Schuco made use of some cutting-edge (and potentially pricey) technology: energy-efficient high-insulation glass, skylights with PV modules and shading to reduce AC load in summer, sunshades to control the amount of sun entering the building, a double-glazed thermal collector field to maximize on solar energy (which produces about 140kW more than PV alone), geothermal heat pumps and rooftop solar thermal collectors.

The company installed geothermal coolers under the building in the parking lot, which draw heat from the earth in the winter to power heat production for the building. In summertime, the flow is reversed and heat is pumped back into the surrounding soil to "re-charge" its heat, while solar thermal energy powers the building's cooling system.

Schuco admits that the payback for a sustainable building with these systems in place is currently around 50 years, which is too slow a return on investment for many organizations.