Last week saw some big moves in the solar industry. Some of the biggest companies increased their stakes in solar, while states forged ahead in the summer heat, increasing their desire for more local solar. Meanwhile, residential installers unveiled even more deals.

The big “G’s” General Electric (GE) and General Motors (GM) both increased their stake in solar last week.

GM made its first investment in an actual solar company. its venture capital arm, GM Ventures, invested $7.5 million in Sunlogics, a manufacturer of photovoltaics and mounting structures, including carports.

In addition to the investment, GM also said it made arrangements with Sunlogics to supply GM with modules both at the commercial-scale level, for manufacturing plants, and another for smaller carport installations at dealerships across the U.S. Already two dealerships have installed Sunlogics solar canopies, dubbed Chevrolet Green Zones, and roughly 100 have begun the process of signing up for such a system, which includes electric vehicle (EV) solar chargers.

Not to be left behind in the solar EV charger market, the other big “G,” GE, partnered with Urban Green Energy (UGE) to develop a hybrid wind and solar-powered EV charger. The device combines GE’s WattStation EV charger and UGE’s Sanya hybrid wind- and solar-powered streetlamp. The companies will roll out pilots later this year in New York City, Bejing and Barcelona. They will make them more widely available starting in 2012.

Other major companies, like DuPont, followed suit. Last week, the materials giant purchased Innovalight, a company that makes a unique solar ink that adds efficiency to silicone photovoltaics. The ink, used with DuPont’s Solamet photovoltaic metallization pastes, can help manufacturers develops Selective Emitter solar cells, which can boost cell efficiency, the company said.

In the latest of the solar sweepstakes going on this summer, Real Goods Solar said it is giving away a solar installation worth up to $25,000. This year the sweepstakes is available to homeowners in California, Colorado, Connecticut, New Jersey, Rhode Island and Vermont. Last year, it awarded a solar installation to a family in California.

Meanwhile, Sungevity is giving away free ice pops as part of its Rooftop Revolution campaign. The company is crisscrossing the Northeast with a biodiesel- and solar-powered ice-pop truck raising awareness of its solar-leasing style low-to-no-upfront cost solar systems. The truck is touring New York, New Jersey, Maryland, Massachusetts, Delaware and Washington, D.C., through early September, hitting local festivals, fairs and other public events.

Another solar leasing company, SolarCity, is now offering EV chargers in addition to its solar leases. The EV chargers start at $1,500, but they can help reduce overall energy use significantly, since home-produced power and grid power cost less than gas.

The New Jersey solar industry may soon face reduced incentives, but for now it’s booming. In June, roughly 40 megawatts of solar capacity in 520 installations was installed in the Garden State, which it said was a new U.S. record.

Another record-setter last week was First Solar, which set a new world record for cadmium-telluride (CdTe) thin-film photovoltaic cell efficiency. It’s now produced cells that are 17.3 percent efficient at converting sunlight into electricity. The record helps bring thin-film photovoltaic efficiency closer to silicon photovoltaics.

Newly enacted legislation in Connecticut could revitalize the solar industry in the state, which shrank after incentives dried up. A new program with tradable zero-emissions renewable energy credits (ZRECs) could bring the industry back to the state.

The new Solar Schools program devised by the California School Board Association (CSBA) and SunPower could save the state of California up to $2.5 billion by going solar. The program was designed to meet the needs of 1,000 school districts and education offices in California.

Image courtesy of NREL.