Solar

Solar energy is Maryland’s largest energy resource. It is a critical piece of the solution to Maryland’s energy supply puzzle - it's available everywhere in the state, can be readily deployed, and can be easily added to our existing transmission and distribution system in parallel with the smart grid roll out now underway. Solar energy eliminates the need for new, billion dollar cost fossil fuel generation plants and their unpredictable, expensive and highly polluting ongoing fossil fuel supply chain to feed them. Clean energy from the sun can be deployed distributed on buildings, carports and small ground mounts where the energy is consumed at point of consumption, or as utility base load via large ground mounted arrays where it provides a predictable cost, clean alternative to fossil fuel generated power.

how it works

Solar energy is energy produced by utilizing the Sun. Solar technology can either convert the Sun’s energy to electricity (photovoltaics), use it to heat fluids for indirect electric power generation (concentrated solar power), or use it to heat water (solar thermal, or solar hot water).

Facts on the Maryland Solar Industry

  • There are currently more than 168 solar companies at work throughout the value chain in Maryland, employing 3,000 people.
  • The 215 MW of solar electricity energy capacity currently installed in Maryland ranks the state 14th in the country in installed solar capacity.  There is enough solar energy installed in the state to power 24,000 homes.
  • In 2014, Maryland installed an additional 73 MW of solar electric capacity, ranking it 12th nationally.
  • In 2014, $221 million was invested in solar installations in Maryland.  This represents a 95% increase over the previous year, and is expected to grow again this year.
  • Average installed residential and commercial photovoltaic system prices in Maryland have fallen by 9% in the last year.  National Prices have also dropped steadily - by 8% from last year and 49% from 2010.

Facts courtesy of the Solar Energy Industries Association

Solar Electrical or Photovoltaics (PVs)

Solar electrical is the direct conversion of solar energy radiation into electrical energy, creating a voltage and current to deliver power. Solar electrical systems typically use photovoltaic (PV) cells or modules to capture the sun’s energy. PV modules are typically assembled into arrays that are mounted on a building or on the ground.

PV systems do not have the moving parts or steam production found in most other electricity generation systems. Instead, the sunlight shines on a solar cell and causes an electric current to be generated directly. Common uses are to generate power in a grid-connected system for use on-site (e.g., residential, commercial, and other buildings, or groundwater remediation); other (larger) systems generate power that is provided directly to electric utilities. PV cells capture energy and then its modules transform it into direct current (DC). An inverter can converted DC to alternating current (AC). These inverters can send power either to the local grid or to an independent system. Very little power is sacrificed in the conversion of DC to AC power with modern inverters.

Ground solar systems can produce energy for a dedicated load, or they can feed an electrical system to which a load is connected. The solar arrays can be fixed in a single position, or they can track the sun as it moves from east to west or north to south, which is one axis tracking, or both, which is two axis tracking. The tracking systems keep the modules pointing at the sun for more hours during the day so that they can capture more energy with the same number of modules.

PV modules may also be built into building materials like roofing shingles or siding products. New thin-film PV technologies use very thin (2 microns) coatings of active material deposited on glass and sandwiched between two glass sheets.  Thin-films can be layered together and coated on other materials.

Solar Thermal

Solar thermal is also known as “solar hot water” because it is an application that uses heat from the Sun to heat water. The primary components of a typical residential solar water heating system are one or two panels, a solar water heater tank with a heat exchanger, a small system controller and circulator pump—known as the pump control module, some insulated piping, and a nontoxic antifreeze for the heat transfer fluid. All systems include some form of backup energy, but electric backup is the most common and allows for a single water tank.

Solar thermal is also frequently deployed at a commercial scale to provide solar water heating for multi-family housing, military installations, retail and industrial applications, and any other application that requires a significant, daily, hot water demand. Largely due to the high efficiency and technical maturity of this technology, the Energy Independence and Security Act of 2007 introduced a requirement that at least 30% of the hot water demand for each new federal building or existing federal buildings undergoing a major renovation be met through the use of solar hot water heating, if it is determined to be life-cycle cost-effective.

Distributed Solar Thermal Technology

This solar technology is primarily used for domestic water heating, pool heating, and space heating.  Solar water heating is the most widely used distributed solar technology in the world today.  Although invented in the US (Baltimore, 1891), this mature technology is largely used elsewhere, leaving less than one-half percent of the world’s solar water heating generation in the US (2008 data).

The primary components of a typical residential solar water heating system consist of one or two panels, a solar water heater tank with a heat exchanger , a small system controller and circulator pump – known as the pump control module, some insulated piping, and a nontoxic antifreeze for the heat transfer fluid.  All systems include some form of back-up energy but electric back-up is the most common and will allow for a single water tank. 

Solar water heaters can also be used to heat swimming pools and spas. In most pool heating systems, the existing pool filtration system pumps the pool water through the solar pool heating collectors.  These are relatively inexpensive, durable, specially formed plastic material.  These systems are highly efficient at the low temperatures required for pool heating.  The water is directed to the collectors by means of a basic differential temperature controller.

When properly sized, systems in Maryland can extend the swimming season several months and increase water temperatures up to 10 degrees or more.  Most pools require total solar collector area on the order of 50-75% of the pool’s surface area.  If this much roof space is not available, then ground mounts are often an alternative. Systems are low maintenance and typically last for more than 25 years. Although there are currently no special incentives for pool heating, the paybacks are generally in the 2-4 year range when comparing to traditional heating methods.

Active solar space heating can be accomplished with similar systems as solar water heating and the systems are often integrated to accomplish both purposes, with water heating being the primary load.  Space heating does require more extensive expertise to design and install.  Consideration must also be given to various types of heat delivery systems (radiant floor is best) as well as heat dissipation in the off season.  This can be accomplished with heat dissipation systems, drain-back systems, or alternative loads like pools or spas.

Concentrated Solar Power

Solar thermal technologies can also be used in large utility-scale power generation systems. Most of these applications involve focusing the Sun’s rays via rotating mirror arrays (called Heliostats) to a central tower core, where the intense heat creates steam that runs turbines to generate electricity.

Solar FAQs

Why Solar?
How Do Solar Electrical Systems Work?
Will Solar Work Well at My Home?
How Much Do Solar Electrical Systems Cost?
What Will I Save on My Electrical Bill?
Are There Incentives and Financing Opportunities?
Where Can I Find a Solar Power Contractor?

Why Use Solar?

As of 2014, over half a million homeowners in the U.S. have a solar PV system.  A solar electrical system can reduce your energy costs and earn credits for excess power generated from peak producing times that is sent back into the local power grid.

Solar energy is Maryland’s largest energy resource - it is available everywhere in the state, can be readily deployed, and can be easily added to our existing energy system without the need for expensive transmission lines or lengthy environmental impact hearings. Did you know . . . that the summer sun in Maryland generates more energy in 1 day than our power plants could produce in 1 year?

Solar is a growing source of jobs in Maryland - over 3,000 professionals are employed by the solar industry in Maryland.  Leading firms including BP Solar World headquarters, SunEdison headquarters, Standard Solar and groSolar are currently based in Maryland. Many new electrical and plumbing contractors that are offering solar technologies as part of their product line are also based in Maryland.

How Do Solar Electrical Systems Work?

Solar electrical is the direct conversion of solar energy radiation into electrical energy, creating a voltage and current to deliver power. Solar electrical systems typically use photovoltaic (PV) cells or modules to capture the sun’s energy. PV modules are typically assembled into arrays that are mounted on a building or on the ground.  PV modules may also be built into building materials like roofing shingles or siding products. New thin-film PV technologies use very thin (2 microns) coatings of active material deposited on glass and sandwiched between two glass sheets.  Thin-films can be layered together and coated on other materials.

PV systems capture energy and then its modules transform it into direct current (DC). An inverter can convert DC to alternating current (AC). These inverters can send power either to the local grid or to an independent system. Very little power is sacrificed in the conversion of DC to AC power with modern inverters.  Grid interconnection is the most popular use of solar electricity in Maryland and is made possible by the interconnection and net metering laws that the state has enacted.

Solar electrical systems can also be used to provide:

  • Backup power: emergency generators and battery use.
  • Ventilation: DC current to turn motors to power fans and provide ventilation.
  • Illumination: stored solar energy can power indoor/outdoor lighting throughout the day and night.
Will Solar Work Well for My Home?

Work with a solar contractor or general professional who understands solar paths and shading to evaluate the viability of solar for you. This analysis evaluates:

  • Your roof's sun exposure - east, west or south
  • The direction, area and inclination of your roof
  • Your current energy consumption

Solar energy systems need 4-8 hours of sunlight per day depending on the season and day length. Solar contractors measure the sun’s position relative to the installation site to determine viability.

How Much Do Solar Electrical Systems Cost To Install?

There are several factors which will affect costs, but generally solar PV costs about $4-$5 per watt installed. Costs have dropped by 50% since 2010.  A complete solar electric system, including panels, an inverter and installation can cost between $15,000 and $20,000. But don’t get sticker shock!  Many cities and counties in Maryland offer low or no interest loans and property tax incentives for the purchase of solar electrical systems.  Rebates, tax credits, and exemptions are available from the Federal and state governments too.  See the MCEC Residential Financial Incentives page for more details.

A growing number of Maryland homeowners associations and communities are joining together to learn more about how to provide their own energy and are creating solar “hot spots” in Maryland through cooperatives to purchase a group of systems, rather than purchasing them individually, to reduce costs.

How Much Will I Save on My Electric Bill?

Savings can run from 50% to over 100% of traditional electrical systems depending on the specifics of your system.  And each year you save more by avoiding increases in fossil fuel costs.

Incentives and Financial Opportunities

The solar industry has received several financial incentives to be more attractive to building owners and those willing to invest in producing their own energy.  Solar Electric systems often increase the value of your home.  Estimates are that every $1000 off your traditional electric costs per year translates to $20,000 in increased property value.

Check our Financing and Incentives pages for information specific to:
•    Consumers
•    Businesses
•    Government Municipalities and Nonprofit Organizations

Finding a Solar Contractor

Maryland is fortunate to have many qualified solar companies throughout the state to provide you with the solar services you need. Here are some things to keep in mind when looking for a solar contractor:

  • Are they licensed as a Maryland Home Improvement Contractor, electrician, HVAC, or plumbing contractor?
  • Does the contractor offer energy audit services or will you need another contractor?
  • What kind of site analysis and consultation services does the contractor offer prior to installation?
  • Does the contractor do both solar thermal and solar electrical systems?
  • How many installations have they done over the lifetime of the company and in the last year?
  • What kind of certifications does their staff hold? Is someone on the staff certified by the North American Board of Certified Energy Practitioners (NABCEP)?
  • How will they help you with incentive and grant funding applications?
  • Does the contractor only install the system or do they also provide maintenance?
  • Are they a national organization or local to the state?

Use the MCEC Business Directory to identify Maryland companies who specialize in residential solar installations.