HELIOS Passive & Active Solar Home - Net Zero Energy
HELIOS Passive & Active Solar Home
General Energy Use, Strategies and Systems
Energy Use:
HELIOS includes passive solar design strategies for maximizing solar space heating (two-story sunspace plus direct gain to mass floors and walls, and earth-sheltering), and a solar hot water system supplemented by a heat pump water heater, plus high efficiency mini-ductless split system heat pumps (operable to -15 deg. F.), and a 9 KW solar PV system which takes care of all electrical needs. This combination of energy strategies results in a Net-Zero Energy home based on actual use over a one year period.
Energy Strategies:
HELIOS uses no fossil fuels (except for cooking), includes passive solar design strategies for maximizing solar space heating , and a solar hot water system supplemented by a heat pump water heater, plus high efficiency mini-ductless split system heat pumps (operable to -15 deg. F.), and a 9 KW solar PV system which takes care of all of the home's electrical needs. This combination of energy strategies results in a Net-Zero Energy home based on actual use over the most recent one year period.
Zero Net Energy Definition Used
Site Energy Use
Monthly Energy Data and Utilities
Energy Data Type: Verified
Electric Utility: Sussex Rural Electric Cooperative
Gas Utility: None
Other purchased Fuels: None
Datasets and utility bills:
Attachment Size 
Energy Use Graph1.36 MB Solar PV Graph 1.33 MB Passive Solar Components 1.66 MB Energy 10 Model - Energy Loads 185.1 KB Energy 10 Model - Comparison 448.98 KB
Datasets and utility bills sources and reliability: Utility bills from Sussex Rural Electric Coop are compared monthly with the actual meter readings.
HELIOS Passive & Active Solar Home - Net Zero Energy
Renewables and Energy Balance
Renewable Energy Sources: Renewable energy is generated within the building footprint (e.g. solar PV on the roof)
Renewable Energy System Description & Details
Original system comprises 22 REC Model REC215 solar collectors with an SMA Sunny Boy 5000US inverter provides 4.7KW (nominal power). Newer supplementary system includes 16 REC model REC255PE solar collectors with SMA micro inverters provides 4.1KW (nominal power). Total system comprises 8.8 KW (DC) nominal power . In addition there is a solar hot water system which includes two 4'x8' flat plate collectors and an 80 gal. hot water storage tank which produces about 2,080 Kwh/year.
Annual renewable energy generated
9,196 kWh
Annual Renewable Energy Generated Data Type
Measured
Power Rating
Renewable Energy System Type(s)
Source of Annual Production Data
8,800Watts
Photovoltaics
Production data is metered -- there is one meter for the original 4.7 KW (nominal power) system (named "Sunset") and another meter for the supplementary 4.1 KW (nominal power) system (named "Sunrise"). Daily reports are prepared by SMA Sunny Portal software.
Storage and Installed Capacity
Hot water storage appears to carry over for several days during the spring and summer, but is quickly dissipated in fall and winter (based on solar hot water monitor readings). Solar space heating in winter months is stored in mass walls and floors until early evening when there is full sun. Based on 32 years of observation, on a cold January day (20 deg. F. outside) with full sun, supplementary space heating in the living rooms is not needed until about 6pm.
Energy Storage type
Solar produced electrical energy is not stored, but solar hot water production is stored in an 80 gal. storage tank which is supplemented by a new heat pump water heater. For space heating, the passive solar direct gain is stored daily in the mass floors and walls (insulated on the outside).
Energy Storage Capacity
Annual Energy Import/Export
Electricity amount (imported from grid)
8,302 kWh/year
Net electricity usage (purchased electricity)
1,922 kWh/year
Electricity amount (credited or exported to grid)
6,380 kWh/year
General Energy Use, Strategies and Systems
Energy Use:
HELIOS includes passive solar design strategies for maximizing solar space heating (two-story sunspace plus direct gain to mass floors and walls, and earth-sheltering), and a solar hot water system supplemented by a heat pump water heater, plus high efficiency mini-ductless split system heat pumps (operable to -15 deg. F.), and a 9 KW solar PV system which takes care of all electrical needs. This combination of energy strategies results in a Net-Zero Energy home based on actual use over a one year period.
Energy Strategies:
HELIOS uses no fossil fuels (except for cooking), includes passive solar design strategies for maximizing solar space heating , and a solar hot water system supplemented by a heat pump water heater, plus high efficiency mini-ductless split system heat pumps (operable to -15 deg. F.), and a 9 KW solar PV system which takes care of all of the home's electrical needs. This combination of energy strategies results in a Net-Zero Energy home based on actual use over the most recent one year period.
| Zero Net Energy Definition Used | Site Energy Use |
|---|
Monthly Energy Data and Utilities
None
| Attachment | Size |
|---|---|
| Energy Use Graph | 1.36 MB |
| Solar PV Graph | 1.33 MB |
| Passive Solar Components | 1.66 MB |
| Energy 10 Model - Energy Loads | 185.1 KB |
| Energy 10 Model - Comparison | 448.98 KB |
Utility bills from Sussex Rural Electric Coop are compared monthly with the actual meter readings.
HELIOS Passive & Active Solar Home - Net Zero Energy
Renewables and Energy Balance
| Renewable Energy System Description & Details |
|---|
| Original system comprises 22 REC Model REC215 solar collectors with an SMA Sunny Boy 5000US inverter provides 4.7KW (nominal power). Newer supplementary system includes 16 REC model REC255PE solar collectors with SMA micro inverters provides 4.1KW (nominal power). Total system comprises 8.8 KW (DC) nominal power . In addition there is a solar hot water system which includes two 4'x8' flat plate collectors and an 80 gal. hot water storage tank which produces about 2,080 Kwh/year. |
| Annual renewable energy generated | 9,196 kWh |
|---|---|
| Annual Renewable Energy Generated Data Type | Measured |
| Power Rating | Renewable Energy System Type(s) | Source of Annual Production Data |
|---|---|---|
| 8,800Watts | Photovoltaics | Production data is metered -- there is one meter for the original 4.7 KW (nominal power) system (named "Sunset") and another meter for the supplementary 4.1 KW (nominal power) system (named "Sunrise"). Daily reports are prepared by SMA Sunny Portal software. |
Storage and Installed Capacity
Hot water storage appears to carry over for several days during the spring and summer, but is quickly dissipated in fall and winter (based on solar hot water monitor readings). Solar space heating in winter months is stored in mass walls and floors until early evening when there is full sun. Based on 32 years of observation, on a cold January day (20 deg. F. outside) with full sun, supplementary space heating in the living rooms is not needed until about 6pm.
| Energy Storage type |
Solar produced electrical energy is not stored, but solar hot water production is stored in an 80 gal. storage tank which is supplemented by a new heat pump water heater. For space heating, the passive solar direct gain is stored daily in the mass floors and walls (insulated on the outside). |
|---|---|
| Energy Storage Capacity |
Annual Energy Import/Export
| Electricity amount (imported from grid) | 8,302 kWh/year |
|---|---|
| Net electricity usage (purchased electricity) | 1,922 kWh/year |
| Electricity amount (credited or exported to grid) | 6,380 kWh/year |