Mercer County, New Jersey: Power, Data Centers and the Local Economy
Home to Hamilton Township, Trenton and Ewing Township
Mercer County sits inside the data center build-out. The SAVRN Data Center Map lists 3 data centers in Mercer County. Mercer County is home to Hamilton Township, Trenton, Ewing Township and Lawrence Township. 1 MW of new generation is planned here across 1 unit, led by Dimension Energy LLC (solar), the 7th largest pipeline among New Jersey's counties. Electrical contractors employ 1,095, up 26.6% since 2019 against up 8.8% statewide, at an average $119,747 a year. Unemployment was 4.9% in August 2026, against 3.4% in 2019.
Cities and towns in Mercer County
Mercer County is home to Hamilton Township, Trenton, Ewing Township and Lawrence Township.
Unincorporated communities (governed by the county): Groveville, Hamilton Square, Lawrenceville, Mercerville, Princeton Junction, Robbinsville Center, The College of New Jersey, Titusville, Twin Rivers, Washington Crossing, White Horse, Windsor, Yardville.
Residents are 2025 Census estimates for the part of each city, town or township inside this county. Census publishes no annual estimate for unincorporated communities.
What changed in Mercer County
1st = the most. Ranks cover counties with a value on record.
| Measure | Then | Now | Change | Rank in New Jersey |
|---|---|---|---|---|
| Population (2020 → 2025) | 386,434 | 399,289 | ▲ 3.3% | 12th of 21 by size |
| Total jobs (2019 → 2025) | 259,842 | 261,312 | ▲ 0.6% | 17th of 21 by growth |
| Average annual pay (2019 → 2025) | $74,508 | $94,418 | ▲ 26.7% | — |
| Construction jobs (2019 → 2025) | 5,439 | 5,727 | ▲ 5.3% | 9th of 16 by growth |
| Electrical contractor jobs (2019 → 2025) | 865 | 1,095 | ▲ 26.6% | — |
| Electric utility jobs (2019 → 2025) | 328 | 486 | ▲ 48.2% | — |
| Data processing and hosting jobs (2019 → 2025) | 420 | 343 | ▼ 18.3% | — |
| Unemployment rate (2019 → August 2026) | 3.4% | 4.9% | ▲ 1.5pts | — |
| Generating capacity added since 2019 | — | 27 MW | — | |
| Generating capacity retired since 2019 | — | 0 MW | — | |
| Planned generation (Aug 2026) | — | 1 MW | 1% of today's fleet | 7th of 7 by size |
27 MW of that came online in 2019 or later, mostly solar. Construction employs 5,727, up 5.3% since 2019. Owners plan to retire 6 MW more by 2035, led by Yardville Solar Farm in 2030. Its power plants have 121 MW of capacity, 64% of it solar. Public Service Elec & Gas Co is the largest utility serving Mercer County, one of 2 with territory here. Its residential customers paid an average 20.42¢/kWh in 2024. Employers here counted 261,312 jobs in 2025, up 0.6% from 2019. 399,289 people live here, up 3.3% since 2020.
Who powers Mercer County
Net change in operating capacity since 2019: +27 MW. Colors follow the fuel legend above.
Utilities with service territory in Mercer County
| Utility | Ownership | Service | Residential customers (systemwide) | Residential price, 2024 | Commercial share of sales |
|---|---|---|---|---|---|
| Public Service Elec & Gas Co | Investor Owned | Bundled | 2,056,231 | 20.42¢ | 41% |
| Jersey Central Power & Lt Co | Investor Owned | Bundled | 1,038,258 | 15.65¢ | 24% |
Customer counts, prices and sales shares cover each utility's whole system in the state, not only this county. Commercial sales include data centers.
Operating power plants 26
| Technology | Capacity | Share |
|---|---|---|
| Solar | 77 MW | 64% |
| Natural gas | 42 MW | 34% |
| Petroleum | 1 MW | 1% |
| Battery storage | 1 MW | 1% |
| Largest plants | Owner | Technology | MW | Since |
|---|---|---|---|---|
| Princeton University Cogeneration | Trustees of Princeton University | Solar | 32 MW | 1996 |
| McGraw Hill Solar | NJR Clean Energy Ventures Corporation | Solar | 12 MW | 2011 |
| Bristol Myers Squibb Lawrenceville | Bristol-Myers Squibb Co | Natural gas | 11 MW | 1991 |
| Hamilton Solar-Crosswicks | Altus Power America Management, LLC | Solar | 8 MW | 2011 |
| Mercer County Community College | Sunlight General Mercer Solar LLC | Solar | 8 MW | 2013 |
| College of New Jersey | The College of New Jersey | Natural gas | 6 MW | 1996 |
Planned generation 1
| Plant | Technology | MW | Status | Year | Owner |
|---|---|---|---|---|---|
| East Windsor Solar 1 LLC | Solar Photovoltaic | 1 MW | Approvals received | 2027 | Dimension Energy LLC |
Scheduled to retire
| Plant | Technology | MW | Year |
|---|---|---|---|
| Yardville Solar Farm | Solar | 4 MW | 2030 |
| Hopewell Valley High School Hybrid | Battery storage | 1 MW | 2035 |
| Trenton Solar Farm | Solar | 1 MW | 2030 |
| Hopewell Valley High School Hybrid | Solar | 1 MW | 2035 |
The Mercer County labor market
| Industry (2025) | Jobs | Average pay | Concentration vs U.S. |
|---|---|---|---|
| All industries | 261,312 | $94,418 | 1.00 |
| Construction | 5,727 | $101,449 | 0.41 |
| Electrical contractors | 1,095 | $119,747 | 0.58 |
| Electric utilities | 486 | $252,896 | 0.69 |
| Data processing and hosting | 343 | $134,865 | 0.42 |
Concentration is the BLS location quotient: 1.0 means the industry holds the same share of local jobs as it does nationally. Industry rows count private employers; cells BLS suppresses are left out.
Data centers and local rules in Mercer County
3 data centers in Mercer County are on the SAVRN Data Center Map.
Mercer County and its neighbors
Of the 6 counties that border Mercer County, Middlesex County carries the most build-out activity: data centers, planned generation and operating plants combined.
| County | Population | Jobs since 2019 | Operating MW | Planned MW | Data centers | Local measures |
|---|---|---|---|---|---|---|
| Mercer County | 399,289 | ▲ 0.6% | 121 MW | 1 MW | 3 | — |
| Bucks County PA | 647,828 | ▲ 3.0% | 2,027 MW | — | 2 | 1 |
| Burlington County | 481,439 | ▲ 6.4% | 429 MW | — | — | 1 |
| Hunterdon County | 131,781 | ▼ 1.3% | 614 MW | — | — | 1 |
| Middlesex County | 883,335 | ▲ 0.4% | 3,067 MW | 16 MW | 20 | — |
| Monmouth County | 651,035 | ▲ 5.4% | 135 MW | — | 6 | 1 |
| Somerset County | 356,486 | ▲ 1.4% | 67 MW | 3 MW | 21 | — |
More of New Jersey
Mercer County, answered from the record
Who provides electricity in Mercer County, New Jersey?
2 utilities have service territory in Mercer County in the EIA-861 2024 report: Public Service Elec & Gas Co, Jersey Central Power & Lt Co. The largest, Public Service Elec & Gas Co, charged residential customers 20.42¢/kWh on average in 2024.
What county is Hamilton Township, NJ in?
Hamilton Township is in Mercer County, New Jersey. About 94,157 people live there (2025 Census estimate).
What county is Trenton, NJ in?
Trenton is in Mercer County, New Jersey. About 91,506 people live there (2025 Census estimate).
What county is Ewing Township, NJ in?
Ewing Township is in Mercer County, New Jersey. About 39,030 people live there (2025 Census estimate).
What power plants are in Mercer County?
26 operating plants with 121 MW of capacity. The largest is Princeton University Cogeneration (32 MW, solar).
How much new power is planned in Mercer County?
1 MW across 1 units in the August 2026 EIA-860M inventory, 0 MW of it under construction or built. The largest owner is Dimension Energy LLC.
Are there data centers in Mercer County?
Yes. The SAVRN Data Center Map lists 3 data centers in Mercer County.
Is Mercer County adding jobs?
Employers counted 261,312 jobs in 2025 against 259,842 in 2019 (+0.6%, BLS QCEW). Construction went from 5,439 to 5,727.
Does Mercer County have a data center moratorium?
No county-level measure is on record for Mercer County. New Jersey has 108 local measures statewide, listed on the state page.